To be clear...
You're saying for real Peltor Comtac 2's just unplug the MT21 (I think it's a dynamic type) and replace it with the Element electret type microphone? Like in this link...
http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWAX:IT
Then the Untied Star U238 plug will work with real military PTT's through the real Comtac2s? Just that simple?