Progress Thread 1989 LX 5.0 convertible - mild project

Scott_S

Active Member
Jan 16, 2022
86
83
28
Rock Hill, SC
Hey everybody!
After years of getting detoured by other cars (Jeep CJ, Plymouth Valiant), I finally got my hands on another Mustang!
I had a GT sometime around 30 years ago. I've been jonesin' for a 5.0 for a while. I'm in South Carolina, not far from CLT, and the market here is kinda wild. I found one that checked all the boxes: LX, 5.0, 5 speed and a convertible.

The car came from out of Spartanburg, SC. A small, private car lot took it in on trade about 4 years ago. The lot owner wanted to keep it for himself, but recently realized he'll never get to it.
He adjusted the valves when he got it and saw roller rockers. He installed a new battery, distributor, wires and plugs and got it running. It's definitely been breathed on. Here's what he told me, and what I can determine for myself:

- BBK shorty headers, cat delete, 2.5" exhaust, H-pipe, unknown mufflers
- BBK 70mm throttle body
- smog pump delete
- aluminum heads, but I can't find any markings on them anywhere
- Edelbrock Performer intake
- unknown cam
- per his words "Stage II clutch" (it definitely has some pressure behind it)
- unknown rear gears
- It feels like it has a short shifter in it.

All power windows work. Power top works. I suspect the top may have been replaced in the not too distant past. Other than being dirty, it's in great shape, fits tight, and I can see some unused staples behind the rear seat and some plastic (like for protection during shipping) around the window frame.
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I'm not crazy about the hood and will be replacing it with, most likely, something stock.
The interior is in better than average shape to be what, I think, is original. I'm missing one seat belt bracket for the drivers side, but the seats sure aren't torn up or worn like so many I see.
All lights and gauges work. Power mirrors don't seem to work, but I haven't investigated it yet.
The car came with new rubber side moulding in the trunk, as well as new weld-in subframe connectors.

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Immediate plans are fresh fluids throughout, just to get a baseline.
The car seems to run good, but most of the gas is old (about half a tank). What do you think about filling it up with some fresh 93-octane and maybe some octane booster and just run it?

Oh, yeah ... it has staggered SVE 17" wheels, too. The tires are old (2011 date code) and show some cracking, so I'll definitely replace them ASAP, too.

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The car is far from perfect, with a few dings here and there. And it definitely needs a wash/buff/waxing. I'll probably rock it like this for a while and then get all the dings fixed and the replacement hood painted.

The underside is in great shape. All sills, jack points, floor pans, etc., are like new and not undercoated.

I noticed something in the passenger wheel well, behind the plastic liner. Is there supposed to be some sort of insulation in there, or have mice made a nest?
Horrible pics, I know, but there's a gray-ish material in there, almost like you'd see under a carpet. Sort of wool-like.

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I've got a lot of cleaning to do, and I'll get rid of a lot of the spiral wire covers, etc.

Other future plans include a nice stereo (for an old man, not for bass thumping contests) and I just love the looks of the Hurst shifter handle in a Foxbody.

Oddly, it doesn't seem to have rear speakers, only dash and doors. How hard is it to add rear speakers in a 'vert if they weren't installed at the factory?
Are there brackets behind the grills? On eBay, I only see brackets for '94-04 cars. Only grills for the earlier Foxes.


I'm open to all praise and criticism! While I've ALWAYS loved a Mustang, I sure have a lot to learn, and I'm not afraid to admit it!
 
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First off nice car man! You definitely got one with some good parts. I believe some of the inner wheel well liners had a grey material stapled to them which is what you may be seeing and thinking it’s mouse nests. As for your back speakers here is a thread on that:

 
First, stock pulleys are fine, hose covers are 'cute', I don't do 'cute' sooooo, the woolly looking stuff is insulation, could not tell wht area that is, IIRC the back of the panel next to the rear seat has some of that stuck to it. Been a minute.
Look at the door sticker, if it's there and readable will have an axle code, also check the housing cover for a tag, no tag may indicate a gear change, then you need to do 'the ol spin the tire, count driveshaft turns' routine.
How many times is debatable, someone, when I was a kid, told me you have to turn the wheel 20 revolutions to get an accurate ratio but now I think they were having fun with me :hide: , if you change the diff fluid look for the gear ratio stamped on the ring gear,
A thing I have done with 8.8 limited slip (posi) drain the rear and fill with diff fluid, conventional or synthetic, your choice, Friction Modifier, Ford has a bottle and I'm sure aftermarket too, find a vacant parking lot and make figure 8s one way and then the opposite, just a few times, it works those clutches clean, now you can drive it like you stole it.
The 91 and 92 verts I had had speakers (factory) in the rear panels by the back seat but I think they had factory premium stereos, look at the back of those panels an see if there are cut outs for speakers.
I have more useless advice, just wait.:jester:
 
I'll take all the useless advice I can get!

I'll check the door tag. I took a quick look underneath yesterday and didn't see a tag on the housing cover, but I'll look again.

The gray padding stuff is behind the plastic, inner fender well lining on the front wheel well.
 
Date - 10/88 = October 1988 build
F0051 = 0051 lbs front accessory reserve load
R0020 = 0020 lbs rear accessory reserve load
Exterior Paint Colors - 21 = Bright Red
Body - 66B = Mustang 2-door sedan (coupe)/2-door convertible
VR - A = Black convertible top
Mldg - XXX = Black bodyside molding
Int Trim - PG = cloth Articulated Sport seating, low-back front buckets (P), Medium Grey interior trim color (G)
Tape - P = Light Charcoal paint stripes
R - 9 = electronic AM/FM search stereo radio with cassette tape player
Ax - M = 2.73:1 axle ratio, Traction-Lok (limited slip) differential
Tr - T = automatic overrdive transmission (AOD)

I think I put the TR - T in the wrong place .... OR, my car has been swapped to a T5!
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Well, it's gonna support that mid-pipe section a lot. Ford thought it was important enough to do it. It takes a lot of the stress off the ball-and-socket joints.

It's also gonna raise the rear of the tranny up by the thickness of the metal, changing your driveline angle a touch.