What are the compression readings? If the compression readings are all around 130 psi, and all within a 10% window, that would indicate no issue with a valve seat. Depending on the engine/head combo, the absolute number may vary a bit from that, and isn't as important as the consistency between cylinders. If there is a low reading in a cylinder, then it could be valve or seat, and the head would need to come off for further diagnosis (as Panic said). But if all the readings are good and consistent, then that doesn't indicate a reason to pull the head.
I've followed your earlier threads. There may still be a valve adjustment issue. Perhaps a bent pushrod. Pushrod check is easily done (perhaps each pushrod has already been checked?). Next is to verify that the valves are adjusted correctly. If all that is OK, are there any symptoms other than the "dollar bill test?"
If I recall, you don't have much run time on the engine since rebuild? Did the builder run the engine or have you run it appropriately to break in the cam (assuming the cam and lifters were all new)?
Hopefully, the questions will help the forum help you get this resolved.
