basically all who own an L series may have noticed that the back end appears to sag in comparison 2 the front. With my rear wheel carrier, fully sick sub woofers

(just being a dick), and anything in the boot, my car seems 2 sit a hell of a lot lower at the rear. My shocks are fairly new and i have king springs in allready.
My question is, is there any suggestions/ideas etc 2 resolve this problem other than putting larger lift blocks in the rear? Im chasing the L series equivalent to putting air shocks in an MY, and why cant we do that?
if it means modifying brackets 2 accomodate a pair of shocks then im up for it.
cheers. Jay