They make different degree wedges that go between
the springs and rear end. i would put a one and a two degree together.
Any spring shop or Summit or Jegs should carry them
You want your rear yolk to be DOWN about two degree from your driveshaft
on your 4 speed car NOT up!
When you drop the clutch the rear end will lift and the yoke will point more
upward than static.
They do not want any excess weight reduction in Stock/SS
they DQed my car in 77 at Winternationals and it took all night to
fab and weld enough of the fenderwell back in from a wrecked 64
from the wrecking yard in Pomona. After that you would have to remove engine
to get header out.
None of the fenderwell headers I have ever bought can
with templates. I wish they did. Maybe they may now as this
was years ago.
Start small a work you way up =It is hard to put the fenderwell back in.
NHRA only allows 1 inch around the header for installation.