Thanks for the input.

DaveSSS, It is a design flaw if all the stems are similar (which I believe is the case). Yes, a machine shop would be cost prohibitive. But I was hoping a headtube reamer/facer tool could be used somehow?

FBinNY, the bottom surface is so far off, I can easily see it when I install the 1inch adaptor shim (that came with the stem). The shim is "sqaure"