Some tips - first off - while you're there and having to drain the cooling system, if the water pump, belt or any hoses clamps are old - replace them then -- easier to do. Second, be sure you have a torque wrench - it's quite easy to overtighten and break the relatively weak aluminum castings of the manifold. Nothing worse than ruining a brand new part. Third - take one of your lower intake bolts and one upper bolt to the hardware store, and buy 4 bolts like the lowers, and 2 bolts like the short uppers. Cut the heads off of all six. You can screw them into the 4 corners of the lower, 2 corners of the upper, and they act as temporary dowels to hold your gaskets in place, and align your manifold when you set it in place. Start a few of the regular bolts, and then unscrew the 'dowels' put the rest of the bolts in and tighten things up. No more than 18-20 ft-lbs. is necessary on the lower, 10-12 ft-lbs on the upper. There is a specific pattern for tightening the lower bolts - and you won't 'guess' it correctly. Get a manual. Oh - use masking tape and a Sharpie permanent marker and mark EVERY SINGLE line you disconnect - fuel, vaccum, electrical, etc. so you can put things back where they belong. Don't assume you'll remember anything.
Lastly, if you've not done a manifold before, I wouldn't undertake it completely alone -- get someone that's been through it to at least look over your shoulder. There are lots of MAJOR things you can screw up that could cost big bucks to repair - mainly in the area of being sure that the coolant stays where it's supposed to stay, and the oil stays where it's supposed to stay. Good luck. Oh - I'd guess the 'book' on an upper/lower intake change is in the area of 2-4 hours - times $50-$80/hr. Gives you an idea of the range of costs you'd likely see for the install. But our guesses don't mean much - you gotta ask the folks who'd do it for you.
If I do get it installed by a pro, how much should I expect to pay for manifold and thorttle body install?
