Guys, I did some writeups on my original website about how I did my swap. I used a '75 truck as a donor. I bolted the crossmember up and washed all the brackets off the '64 rear and welded them on the '75 rear. Here is the link:
http://home.mchsi.com/~bkndsdl1/front_end_page_1.htm
Hope this helps!