I'm with Grigg on this one too. The 63" 14 bolt is by far the easiest to come by. Trust me, I've been crawling around junkyards for the last several years with a tape measure. Finding a Dana rear out of Dodge or Ford van is just about a lost cause. I've only seen one Dodge with the narrow Dana in about 5 years. I've seen a ton of Dodges with the semi-float 9.25" though. Same with the Fords, I actually have yet to even see one with a Dana. Most likey you'll be looking at a Sterling semi float or full float Sterling. Trying to find a 67-72 center section is futile also. Even if you find one, the best gear you can hope for is a 4.11. Get ready to write a big check too, it won't come cheap.
I have pics of a couple 14 bolts. One is a 67" and the other a 63."
www.photobucket.com/whitedog76pics I got both of them for $300 on Craigslist.
