If you have enough carbs to use on the 5 carb setups, you might try progressive linkage with 2 carbs as "primaries" and the other 3 as "secondaries".
If that proves to be too much carb, you could try a pair of 81s as the primaries.
Not that I've thought much on running 5 carbs on a Jimmy before.
It'll look cool regardless of how many you actually use.
A super T-10 might hold with the 5.13 gears (the larger the number back there the easier it is on the trans).
The big thing is the torque of the 302 is a lot like a diesel, it all comes in so muck lower than what people are used to today; it makes it great to drive, but can be exceptionally hard on the rest of the drive train.
Best of luck.
