Buy a take off spring pack from Boyce Equipment, Memphis Equipment or TNJ Murray. That's what I did. Ask for a hand picked unit with as little rust as possible. Broken springs are common on these rigs. Of course you could rebuild yours, but there are complete replacements available . I paid 200 $ shipped for a almost NOS take off unit. GM had problems with the rear springs cracking for a while then improved their quality control. The stock rear springs are beefy units.