Where? I found a bunch of post 95 axles, which will have 29 splines instead of 27. Everything appears to be for Jeep, which may or may not make a difference. I don't think aftermarket Jeep axles will be weaker than my 100,000+ mile, 50 year old stock axles, but the metallurgy may have been engineered for different loads. I'm just taking a wild guess, but it seems like the axle would see different forces from a muscle car doing burnouts than a Jeep crawling rocks.
AFAIK every year up to 95, when the spline count changed to 29, should interchange. If 8 1/4 owners have to shop used though, how many junkyard axles are still out there, and how long will it last?
A forum member on For B Bodies Only suggested I have 8 3/4 axles custom cut for 29 splines, and use a 29 spline differential, which is why I was trying to find out if there were any other changes made in 95 that would prevent the 29 spline diff from working in the pre-95 axle.
I spent a few hundred buying upgrade parts for the 8 1/4, only to get hung up on this question. I've been thinking about putting a 27 spline diff in and using the weaker axles as a temporary solution, but it doesn't look like that's going to work either. I was hoping to keep the car light and efficient (for what it is), but I may end up doing the typical thing and swapping in the 8 3/4 or Ford Explorer axle.