Need 4 speed advice

I have done this recently with my own car! I personally used the 64 /6 4 speed ball and trunionwith NO problems[warmed over 340 .528 solid cam,4 speed,391 gear w/ suregrip] but i plan on going to my driveshaft shop and getting an adapter for the transand hooking up a 4x4 pickup style[rear]drive 2 piece driveshaft.I also plan on using the newer style ROUND POLY MOUNTand crossmember found on 73 and up darts,new yorker,and diplomats that also would allow for dual exhaust.64 and65 transmission crossmembersare squared on one end. Oh yea the ball and trunion were also available on the coronets with big blocks and hemi's. I personally think there was nothing wrong with the ball and trunion it was merely different so they went with the slip yoke style across the board. that is my 2 cents worth...I hope I helped. I wish I knew how to post pic's cause I sure would have to post ALOT OF THEM!!!