$1k without a locker isn't that great a deal, but at least it's geared right assuming you have the 4.90's.

I run stock shafts and 760X ujoints in mine with crawler gears and haven't any trouble with shafts (yet). Not sure what Carlton meant by "wedging it in the crack", but if it's fully wedged, you'll break an aftermarket shaft in that scenario too with the right gearing.

I'd opt for the spring packs in back, or better yet, cut and reweld the perches and go SOA in back.