Shop says my computer is fried!!????

Well got tired of trying the eec test with nothing but a solid light on so i took it to the shop. They say they can't test the computer and that its fried. Can't i just buy another from a mass air, 5-speed 87-93 stang and put it in? Symptoms of car are: runs rich, bucks and misses sometimes, won't start after 15 min of driving takes 4 hours for it to start again, terrible performance and barely spins tires from 5 mph take off, and last it smokes bad when i punch it. Should i insist on buying the computer myself or let the shop charge me an arm and a leg to buy/install one? Can i install one easily? They did compression check and got over 100lbs to each cylinder so am i still good on motor? Is the compression good enough for some bolt ons?
 
Try Automotive Computer Rebuilders - 800-254-3556. They are located in south Florida. Be prepared to haggle over price and delivery times, and you can get a reasonable deal. He has a 2 year warranty, but be sure you hold on to your paperwork.

Ebay will have computers for $75-$125, but no guarantee. The local junkyard may be a little better in that if it doesn't work, you can usually return it.

The computer isn't hard to remove & re-install. You remove the passenger side kick panel, remove one 10-32 machine screw and rachet off a 10 mm bolt that holds the wiring connector in place. Installation is the reverse, putting the computer back takes a litte wiggling to get it seated in the mount. No special tools or setup are required.
 
Well the shop says they can get a NEW computer for 150 and install will probably cost bout 50. Bad thing is my dad already told him to order part so i guess i'm stuck with it now. Does that sound reasonably though? I hope the shop was smart enough to get one for a mass air 5speed. We'll soon find out.