Whats the point of all this modification? You want a gigging tonewheel hammond, but with waterfall keys?
To answer your question, you can chop it as far as you're willing. It IS all possible.
Mine
and most everyone else's oppinion will be to find an M. no point in
dumping that much time, cash and profanities into a worthless L. But
then again, people do things that aren't quite efficient because of
some fever we all have for hammonds. Be aware that the chopped spinnet
will still be quite heavy.