Sanitizing a 71 C10 with a mishmash of engine parts

[dglaser]

I need some help in figuring how to sanitize a truck that I inherited from a family member.

Basically, it is a 71 C10. It has a THM350 for the tranny.

The engine is a curios case. The truck originally had a 350. However, the engine died and it was replaced by a 305 from a 76 chevy nova. But wait there is more. Evidently, the manifold and carb of the 305 was replaced by a manifold and a two barrel carb off of a 350. I am sure that the carb is off of a 350, I'm not sure about the manifold.

The truck makes terrible gas milage - approx 10 mpg. And is not drivable until the engine gets really warm.

So, would like to replace the manifold and carb with something more suitable.

The problem I have is that up here in the north east, it is really hard to find trucks of this vintage. So I figure I will just have to buy a new manifold and carb.

The goal is to get better gas mileage and improved drive-ability. Improved acceleration would be nice.

Any suggestions on the manifold/carb combination?

-David