its been done but its quite a bit of work for the front. most of the work would be reinforcing the upper shock mount to be load bearing for all that weight. you will also have to fab a large open upper control arm for the bag to pass through and the lower can still be used but it will need a plate welded and reinforced to hold the bag. the back is pretty easy just some square stock, plate, and front bushings. use the square stock to make arms from the front mount to the axle and make pie cuts to get the pinion angle correct, then all you do is weld up a plate to the arm near the axle for the bag and another to reinforce where you want it against the frame rail area. oh and don't forget the panhard bar.
