OOHHH... time to be buying an old manual off of the samba... :wink:
Dunno, myself. I have worked on the internals of a 36hp once, the rest of the work (very little at that) has been outer work, tune-up, etc....
A 40hp is close enough to the later 1300-1600 to get by, but, like you said, the 36er is a different ballgame.