hhhhhmmmmmm? Best place? I'm not sure there is a best place. But if you ever fine the best place let me know. What you might want to think about is the truck as a whole before you jump off and want 30+ inches of wheel travel... Make sure the front end will keep up... and that you have enough wheelbase to handle that much travel Once you do that then you have to think about the Spring and motion Ratio. I take it you will be using a coil over.. If you run the thing to far up the arm you might have a problem getting springs for it.. or you will work the shock into coil bind with a heavy spring rate far up the arm. I personaly would try and use at least an 18" stroke shock and get it as close to the rear end as possible up the arm. In my experiance shocks seem to be alot happier as close to 1 to 1 ratio as possible. Then again It is just my 2 cents and lots of guys might tell you differnt. Good luck..