The Rockstomper bumpstop extensions are shorter than those with the lift kit. This creates a larger space between the bumpstop and a-arm allowing the a-arm to travel upwards farther.

If you go to the tech section, there's an article on cross linked air shocks. It has a drawing of the bumpstop extensions I made for my truck. Check it out, might save you a buck and the ones I made are much stronger than the Rockstomper set up. They, of course, require a little time and labor to fab up but depends really what you have more of I suppose, time, money, etc....

Also, the cross linked air shocks will allow you to use all that new travel. Otherwise the t-bars are very stiff and will limit flex.

Frank.