is this too good to be true
 

This guy on craigslist has 4.88 Spicer gears for a Dana 30 for 50 dollars that's cool but he also has a Detroit locker for a 29 spline 8.25 for 50 dollars so what should I look forto make sure it is solid he took out out because he put in arb instead

Well.. 50 bucks may be low enough to wanna take the risk.. I guess it's kinda like throwing parts at a problem hoping that you will just happen to replace the right part eventually.. Point is, it's a 50 dollar gamble... Your call, but if it were me, 488 bucks and a guarantee that I'm not getting ****ed with no lube is totally worth it... Different budgets, though, this is just me spitballin... Good luck!

Pry stolen...
That being said, If its a true Detroit locker in working fashion I would buy it...

No 4.88 gears

You better get on that or it will be gone...

Make sure it has the right carrier break for your gears.
If not, you could always buy it and sell for like 400 bucks. lol

No carrier break on the 29 spline C/8.25 one Detroit locker fits all ratios.