This fellow has a set of the proper frame towers for your truck.
http://67-72chevytrucks.com/vboard/showthread.php?t=397681
if you cannot find these there is an alternative by using the motor crossmember out of a 67-72 4 x4 . advisable if yiou are going an automatic
ron
I did use the later setup in my 64 as I had looked for years for the 230,250 or 283 passenger side frame tower . have pic if you ;ioke

Last edited by padresag; 10/11/2010 7:05 PM.
http://s908.beta.photobucket.com/user/padresag/library/turned%20works
http://s908.beta.photobucket.com/user/padresag/library/furniture
and a little history of where I come from
http://forum.woodenboat.com/showthread.php?156542-old-boatshop-in-Steveston