As an alternative, have you thought of getting a correctly rebuilt
Q-Jet? This Car Craft article describes the process from JET.

http://www.carcraft.com/howto/57178/

I bought one from them for an 85 Chebbie truck and it was great. JET
asked me about the engine detail and built the thing. I bolted it on
and set the idle speed and it was perfect. These guys know their stuff
on Q-Jets.....and the mileage was mucho improved. Plus, I didnt have to
jack with the manifold, the linkage, the fuel line, etc. Highly recommend
them. Advice: call them directly and buy it directly....dont buy the
Edelbrock stuff.....more $$

Mike in Tucson