Got some good news, I weighed my stock rear leaf springs and compared them to my 4 link with watts from gerst.
Left side spring 42 pounds, right side 40 lbs, add 5 lbs per side for the shackles and such. Plus 7 lbs for the rusted out shocks, 6 pounds for the spring perch plates. Total weight 100 pounds.
The gerst weight: including everything, all the links, brackets, coilovers, 78 pounnds!!