ill tell you about it it is a 1988 chevy 2500 6 lug with 33x12.50r15 it was a diesel when i got it it had a 81 350 bored 60 and a sm465 4 speed with granny rpo code says it has 342 gears it has a holley 670cfm carb i ported the heads gasket matched i want to make it get about 20mpg currently i get 10 if lucky and i try to be easy like shift at 2500rpm ect hiway 2k at 50mph my only idea is to go to johnys u pull it and get a 5 speed for it im on the hunt for a quadrajet too as it is set up old school hei dist 4bbl not fi