Al,
I have several different adjustable sights (Bomar, Micro, Meg Gar, S&W & MMC). So far the old style MMC for the 1911 looks the most promising. I have managed to accumulate a half dozen or so of these. I have dovetailed one of these into a rear toggle and it seems to be working ok.
<img border="0" alt="[king]" title="" src="graemlins/r.gif" />
I haven't decided whether to try to add this option to these two guns or not.