What ever you do, don't get the 5000's. Best thing I ever did to improve the ride of my truck was taking them off!
If you don't want to change the stock mounts, i'm assuming that you aren't trying to achieve a lot of suspension travel either. In that case there's a lot of other choices that will probably do just fine for you. 9000's, you can adjust em. Pro Comps, they're cheap, etc. and no modifications.
I'm taking off the 9000's and goin with the bils.
Good luck.
