What is the difference in frames from a 71 to a 90. Me and a friend are going to swap trannies and t cases. He will be taking my 700 to 241. Will my crossmember work for him or what will we have to do? And will a crossmember for a 465 to 205 work on a t350 to 205 adapter. Also how good is a 1971 27 spline 205 and will it work with a doubler?