Just thought I'd share where I am right now with my rear axle conversion. My 55.1 stock rear end had gear problems and rather than rebuild, I decided to swap to something a little stronger and newer. After some good feedback from this forum, I decided on the chev 14-bolt (9.5" ring gear) axle because of availability. The following is some info:

1. Drum flange to drum flange is 64" vs the stock 62"
2. The spring saddles have been removed from the top of the axle and will be relocated to the underside.
3. I will likely relocate and re-use the 14-bolt lower shock mount brackets.
4. The 14-bolt uses a 1350 u-joint. I am looking at using a conversion u-joint (1310 to 1350) but I may have to get a new driveshaft fabbed because the current driveshaft may be too long now.
5. I plan to use my Eagle rims (6-lug 15x8's with 2 1/2" backspacing)with 245 or 25570R15 radial TA's. I hope I don't have rear fender clearance problem (I may have to modify/extend the fenders).
6. The 14-bolt sure is a lot heavier than the stock 10-bolt! The drums are impressive too.

I would appreciate hearing from anyone who has already done this conversion. I think it is all going to work OK but it is good to hear others' experience.