are you installing factory rubber or polyurethane? there will be a differance in the way you install them. anyways you can put the jackstands behind the springs on the frame and it will be fine, you need the springs to be as free as possible to put the pivot point back in correctly but i would suggest that you plan on loosening up your leaf spring u-bolts to do the job(it will make it easier to do,trust me) where your leaf spring is designed to not only hold your trk up but to also keep your frt axle straight (hense no panhard bar) the springs will try to hold the axle straight, not alowing you to move it around to get bushing out. now with the factory bushings you have to take the bushing out with the metal sleeve (not that bad) with the poly bushing you reuse the metal sleeve (you take a torch and burn the rubber out and then clean the metal bushing from any left over rubber) either way plan it for a day of work (it wont take that long but you are working on a trk that is 15 years old)