Dittos on what Truckernix sent... with one advisement...

I used this kit on my 51 1/2 ton panel. All good quality stuff and straightforward
installation. However, after a about 400 miles in this set up
(455 Buick Stage 1 w/ T400, and a 56 Olds rear end)
I find the truck wallows just a bit too much out back for my liking.

I think the problem is that the panel weighs a LOT more out back than a pick up;
and this kit is engineered for pickups. The kit moves the shocks well inboard
of the springs. I am leaving it all in place but, will be re-installing shocks in the original locations. This should provide needed stability "outboard" of the frame that a panel needs. This would then allow me to convert the new inboard shocks to "airshocks" that would provide a bit more support when I'm towing or hauling heavy loads.
I'll report in when I get this done