Please HELP!!!!!

Those 901 Comp springs are single springs with a dampener. Are you positive your springs are 1-3/8 diameter. I thought all stock springs (except magnums) are 1.437 diameter which is close enough to 1-1/2 so you shouldn't need any spring seat milling. My 340 X heads were stock when I got them and you can put 1-1/2" springs on them with no problem.

Now if you were installing dual springs you would have to have them cut but were not talking dual springs here.