Hi friens I'm rebuilding a '77 C30 truck, I will swap the inliner with a 96 carb 350sbc. The Dana70 rear end(canadian version) is 4.1:1 and has very much wear, since I have to rebuild I wonder if changing to 3.73 for better mileage and lower highway RPM or keeping 4.1 if somebody can help me feel free to do it