remove the coilovers and go back to the stock suspension.
If you want a compliant drag like rearend setup, make the suspension as loose as possible. 90/10 shocks in the front. 50/50 in the rear. stock springs, shouldn't be a problem.
Had a few enquirers into the condition. As such i'm taking these to Tighe cams tomorrow, to see if they can be used after a quick linish, or will need to be reground.