Before that, gotta get cutting...Gotta cut out and grind the steel spring perches on the axle...leaving the truss for my upper links.  I gotta make space for the heim shackle coming off the snail wrap. So Gotta grind and then weld in new perches for the spring to connect to the axle.  The stock spring mount on the frame is a no go.  Gonna cut that off and build a new one out of 3/8 steel and french it into the frame.  Then I gotta sleeve the end of the springs and and run a bushing through all of that.  So it's gonna be hinged at the frame.  Then a heavy steel bumpstop will come off the frame near the upper spring mount and bump against the spring.  When the truck sits at static it will always ride on the bumpstops, the shackles will allow for generous up-ward movement.  Since it will be hinged at both ends nothing will limit it's downward movement except limiting straps.  And of course I have to factor in the 4 link and try to make the axle swing in a circular movement through the up and down stroke.  Whew, lotta to do.