I've got an ST2 I nabbed for reasonable given its condition, engine is non running and I plan to give it a teardown/overhaul.  The genhead is a Kohler 7.5kw and is basically shot.  From what I have gleaned the Kohler head isn't worth messing with anyways.  The issue I'm wondering about is, this appears to have been a start-o-matic unit using the genhead to start.  I have not pulled the access panel yet to see if there is a ring gear on the flywheel to convert to a automotive starter, if there isn't can these be sourced considering it is a reverse rotation unit?  Also it appears the Kohler set up may not be a standard SAE housing but something custom, how difficult is it to couple a newer style brushless head like from Yanan to this unit?