Coilovers would be your best bet, Just putting lowering springs by themselfs would sierously harm you handeling, you would either need Coilovers or A Matched pair of lowering springs and uprated dampers
Ventura springs go very low but your worn shocks won't last long. Best bet is either coilovers or some replacement shocks like Koni with some suitable springs like Whiteline/Tein. Lowering springs will give a better stance but the ride quality will be poor and the car won't handle as the spring rates are not designed for the shocks.
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