Another pinion angle question

Trans is 2* down so pinion should be 2* up. Got that at rest no shims.How many * should I allow for 4456/4457 s/s springs in a 3400 lb coronet? Should I add a 4* shim to be 2* down at rest and run the snubber close to the floor to limit the axle wrap under accelleration? Or do I need more than 4* difference between pinion and yoke with s/s springs at rest? What i,m trying to say is will the springs flex more than 4* under normal driving power. I can control wrap up under launch with the snubber.