Currently on my CJ5 i'm running 80-88 toyota P/U rear leaf springs. they are about 48"s long w/a 4.5" offset center pin. I'm looking for new springs as these are bent. What springs have more offset so i can move my axle even further back? They can be longer as i'll likely have to stretch the frame some anyway. I've heard f150's are offset 6"s but how long are they.