I would like to know. can you get high geared rear ends for the P30 chassis? someday I would like to get a higher geared ring and pinion to get the rpms down a little. anyone ever done that?
Ring and pinion, No. You will need the low ratio at some point. That leaves you two options, newer model transmission with overdrive and aftermarket electrical control or a overdrive auxilliary transmission like a "GearVender". Both options will be expensive even doing it yourself!