I`m getting close to completing my build on my `70, but am wondering which carb I should go with? The intent of this rig is going to be 80% off-road and 20% street. Specs are as follows, 351W, T-18, D20 I am running 5.38 R&P. I don`t wan`t to swap to a four barrel because if I do that I`d might...