Originally posted by Boo Radley:
It's easy enough to convert to a 12 bolt out of a 67-72. I'm not 100% sure the wheel bolt patterns are the same but I think up through 1970 they are. After 70 they went to the 5 lug wheel.
Boo Radley 
Well, actually, Boo, when I got the truck it had a late '70s 12-bolt rear axle. I got a stock '59 Chevy truck rear axle for it which has a 3.90 gear ratio, which is perfect for me, since the late '70s 5-bolt axle has a 3.07 gear ratio, and my 700 R4 tranny has a 30% overdrive, and a 3.05 1st gear. So, yeah, if push comes to shove and I really have to have a posi, I can always go back to the 12-bolt axle and get a new ring and pinion while I'm at it. But I really like that 3.90 ratio.
Does any body need the 235 six and grandma 4-speed floor-shift I took out of it?
