I don't see anything wrong with it. Looks great from the pics.
Very uncommon "No-option" GT although it does have air-conditioning. What year is it? No dash emblem and lack of mass air meter tells me it's an 87-88, however it has a 140MPH speedometer in it, which didn't appear until mid 1989. SO it's possible the mileage on the speedo is not accurate.
Engine looks stock other than the BBK cold air intake. A/C looks like it was converted to R134a at some time. Who knows if it's works.
Looks like a great car. I'd park it in my driveway. I'd ditch the BBK and put a stock airbox back in and work to just clean it up and enjoy it.
No. It is a factory speedometer out of an 1989. In 1990 the cluster shape changed, so a common mod on 87-88 cars originally equipped with the 85MPH speedo is to swap in a 1989 140MPH speedo.
SOme people match the miles to the original cluster, most do not. So keep in mind the displayed mileage may not be accurate. See if the owner has paperwork on the speedo swap, unless the mileage doesn't matter to you.
If the idle is smooth, it runs well, and rust is not an issue, then look for missing smog equipment (cats and the air pump are the big, obvious pieces) and hack job wiring under the hood and dash. Also check the spare tire well for rust and the jack. See if the shocks and struts are leaking or are bouncy and if the power locks work and he the weatherstripping is.
We can only do so much inspection for you from the pictures. If you are new to Mustangs or are not confident in your automotive diagnostic skills, do you have a shop you can trust to do an inspection?
The car looks really nice, to be honest. The only problem is that none of the pictures are of the common rust areas so it is hard to say...
Strut towers, door hinge area on the unibody, rear subframes, and the cowl are all need to be closely inspected for rust. It can be repaired, but rust repair can get very expensive and/or very time consuming.
If the body is clean and rust free, the rest of these cars are pretty easy to work on and I wouldn’t be too worried about getting it fixed.
If you are in snow country, put the car you are interested up on a lift and examine the underside VERY carefully for corrosion. The front shock strut towers need close inspection and some strong light to assist in the inspection. Sight from the front of the car to the rear along the sides of the car to make sure that the body lines are straight and match up. Use a magnet to make sure the rocker panels and doors aren't Bondo'ed up excessively.
If you are in California or some other area with strict emissions laws and buy a car, part of the deal should be that the owner takes the car and has it emissions tested. If it passes, you buy the car and pay for the emissions test cost, if any. If it does not pass, walk away from the deal. For a mechanically inexperienced owner, emissions related problems can be difficult and expensive to fix. Avoid any car that was originally EFI and has been converted to carb like the plague. That's often a clue to the fact the previous owner had problems and the resulting hack job has MORE problems.
Keep in mind that areas with strict emissions laws may make the go faster goals more difficult to reach. Some parts are OK to replace with aftermarket parts and others aren't. Check carefully before you get out your wallet and buy something you can't use in the area where you live.
If you want to do the fix up & power up thing, make sure that you have some other form of reliable daily driver. That way the stang can sit while your wallet and hands take a rest from the last project that didn't quite get finished on that 3 day weekend. Things always cost more and take longer the first time you do them. Having some other working vehicle makes life easier since it isn't the big crush to get it running for the Monday morning drive to work or class.
Plan on spending some money on tools it you don't already have them. The stang has both metric and American fasteners, so you really need two sets of wrenches. A timing light, digital voltmeter, vacuum gauge, compression tester, fuel pressure test gauge and fuel line coupler tools are some of the test & tuning tools you'll need. Visit the pawn shops; sometimes you can find deals on tools & test equipment if you stick to well known name brands.
A sheltered work area is almost a must, someplace that you can leave the car in pieces without upsetting anyone. Some guys here have changed a transmission in the parking lot of their apartment in a rainstorm, but they will tell you it wasn't fun. Depending on where you live, a warm dry garage is a nice place to do the winter projects that stangs tend to become.
EFI (Electronic Fuel Injection) Computer - every stang after 85 has or had one: don't let it intimidate you. The computer based EFI systems are not hard to fix and most of the time they tell you what's wrong with the engine. Here's a book that will get you started with how the Ford electronic engine control or "computer" works.
Ford Fuel Injection & Electronic Engine Control 1988-1993 by James Probst: ISBN 0-8376-0301-3.
It's about $35-$45 from Borders.com see http://www.amazon.com/ . Select books and then select search. Use the ISBN number (without dashes or spaces) to do a search
Use the ISBN number and your local library can get you a loaner copy for free. Only thing is you are limited to keeping the book for two weeks. It is very good, and I found it to be very helpful.
Things that break often:
T5 5 speed manual transmission (syncros go bad, mostly 3rd gear)
TFI Module (Thin Film Ignition module - mounts on the distributor)
Electric door locks (see the link in my sig for a cheap & easy fix)
O2 sensors(oxygen sensors) They are good for about 60,000 miles and start to go downhill after that.
TPS Sensor (Throttle Position Sensor) causes flaky problems with idle & acceleration.
Fog lights -they overheat the wiring and cause the headlights to flicker. The fix is cheap and simple if you can do electrical stuff.
Harmonic Balancer – they separate between the hub and outer ring. A harmonic balancer puller is a must have to change it. You can rent or borrow a puller from most of the larger auto parts stores.
Things that are very durable: Engine - as long as it hasn't been abused, it will run good for 150,000-200,000 miles without an overhaul
Rear axle - other than an occasional case of worn clutches in the traction lock, they almost never have problems.
Computer - believe it or not, the computers seldom have problems of their own. Most of the problems are with the sensors and the wiring.
Suspension – the front and rear suspension has very few problems if the car hasn’t been wrecked or seen a lot of drag strip runs. The drag strip runs tend to distort and tear the mount points for the rear axle control arms. Revving the engine up to 4000 RPM and dumping the clutch with slicks or drag radials tends to break things.
Things that don’t break often but are hard to fix:
Water pump mount bolts – they corrode and shear off when you try to change the water pump.
Rear oil seal on the engine – lots of parts to remove to get to a $20 seal.
Power steering pump – the pumps are noisy and the pulley requires some special tools to remove and install. If you have the tools, they are easy to do. Again, the larger auto parts stores will rent or loan the tools for the pulley.
Power Steering rack - it is hard to get the toe in set so that you can drive the car to the shop to get it properly aligned.
Starter – the top bolt is hard to get a socket on if you don’t have the right combination of socket, universal joint and extensions.
Everything considered, 5.0 Mustangs are not hard to work on. They just require some patience and thought before you get started.