Does anyone have any experience with the 700r4 tranny? I am considering putting one in my 70 3/4 ton hooked up to a sm blk 350. I will be using the truck to tow my boat, as well as regular driver and like the overdrive for gas mileage. I currently have a manual in it. I know I need to get an adaptor for the transfer case. Does the tranny have a good rep--or would I be better off going with a th350--400. If so why?