looking for 4.10s for my 9.25. which set would be best?

Randys ring and pinion
http://www.ringpinion.com/b2c/Cart.aspx

summit racing - motive gear
http://www.summitracing.com/parts/MGR-C9-25-410/

summit racing - richmond gear
http://www.summitracing.com/parts/RMG-CR925410/

also do i need the one with 12 or 14 cover bolts, 29 or 30 pinion spline count, and 1.875 1.876 or 1.877 pinion shaft diameter?

thanks in advance

 

There should be a tag on your diff that tells what you have.

 

you have the 94-01 chrysler 9.25 and they're all the same and have a 12 bolt cover. but don't get it confused with the 02 and up FRONT axle which is the AAM 9.25.

1.875 1.876 or 1.877 pinion shaft diameter are all the same..

also check Complete Offroad.
and you'll need a Master Install bearing kit for about $100-150.
and unless you have a buddy that knows how to do this, you'll need an expert install which can be pretty expensive, $400-600.