Don't change anything
Default maleShep head model is special, of higher quality. You can't rebuild it through customization, or slightly change it. It's all or nothing.
You can definitely change his class and history without changing his face, though. If not, you can get it by cycling through the various default faces (on ME1 at least). It should still be the high-quality face, but I don't know for sure. Delspencerdeltorro 04:19, October 27, 2011 (UTC)