I agree. If the newer 8-speed trans were mountable to the 4.7 I'd go for it. Better acceleration and gas mileage. But a 545REF or 65RFE basically have two overdrive ratios for highway driving so its still better than 5th gear with my current 5-spd manual trans. When I install the 4.7HO and 545RFE in my 56 Dodge pickup build I'll have to get a driveshaft made for it so the tailshaft length of the trans is not an issue that way.

I'll also have the option of going to an aluminum driveshaft or some other drive shaft options.