273 adjustable rockers need refurbish.

Then you have other issues. .009 difference in valve heights doesn't amplify into a .080 difference in preload problem. The preload difference is coming from somewhere.

-Your pushrods are bent
-Your block deck height is inconsistent by checking 1,2,7,8
-the heads weren't shaved consistently
-measurements are inaccurate

When you're checking all this, the head is torqued down with the gasket to at least 50% torque? Is there any way that the dowels in the block deck are damaged or mushroomed, preventing the head from sitting down flush on the block with less than 100% torque?