I don’t have any factory lit. and I’ve never had or worked on one.
All I can off comes from my picture files. There seem to be a
flange that attaches the exhaust pipe to the cylinders and it looks
to slip in to the casting attached to the gear case. If this is not
what your seeing on the motor your working on I suspect some
modifications have been made. Wish I had more to offer.
Tubs
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.