Hi. I am changing the rear gear set on my 46 ford coupe. I want to be able to cruise at 65mph without feeling that i am pressuring the engine. But I also want it to be usable in low cruisingspeed in the city... and to pull my 1000pound vintage speed boat. So here`s the question..... should i choose the 3.54:1 or 3.25:1 ? And is the gear set from speedwaymotors any good? Other shops that sell this? PS. 100hp flathead, original 3speed trans 15" (6.70) tires. What do you guys with 30/40`s fords use, and what do you think? Thanks guys!