i personally do not recommend getting moser axles. i have seen plenty of them twist and brake where a stock axle wont twist. for the same money you can get axles from strange that will be a much better axle. go with 31 spline. going with a 28 spline 9" is a waste. you would be better staying with the stock 8" that already has 28 splines. gear ratio is a tricky thing to figure out. in the end it really depends on what results you want in all the different possible uses. i would say any ration between 3.25 up to 4.57s. the 3.25s if you are running a shorter tire 24"-26" and will be doing allot of freeway driving. the 4.57s if you are running a tall tire 27"-29" and just want to drive on the surface streets and drag race.
I didn't know that about mosers. I personally have strange axles going into my maverick but I bought them a very long time ago. I was going to go with moser for my falcon but now I'll have to rethink that.
moser is a company that spends allot on adverting. allot of there products are great. most of those are not made by moser them selves. what i have problem with is there axles, and there gm 12 bolt castings. the do make really good housing ends. they have allot of different ones to allow you to use what ever stock brakes your car has with a 9" style bolt in axle.
If you want to go 31 spline, you might luck out and get a good pumpkin and posi already put together. Trucks came with 31 spline stuff, as did the better car 9 inchers. Shop the swap meets and boneyards, once you figure out the gear ratio you want. Posis can be rebuilt.
also whats the best swap meet around here in north florida? i see your from clearwater.... turkey rod?