Ok I've got 35yr old SS springs and they're getting saggy. Years ago weighed far at 3650, assuming I need a pr. of 3600#. I've already got the extended frt.hangers so I figure to save some money. Any thoughts on using 2rt.side springs so it doesn't lean? Been reading horror stories about rear being a mile in the air,spring arch not lasting,etc.Originally when installed the rear was not much higher than stock. Ideas?