The propblem is keeping them wet on the back of a cat. They get alot of air time and dont like it.
Pantera1; Where are you finding fat shaft 1:62 sportmasters for $2K? Ill take a pair at that price today.
2nd pic is a 20min old snapped propshaft

Prop shaft gone

They were small shafts ..There was a guy out in AZ that had them as spares .. keep your eye peeled on scream and F unless you want spankin new from merc $$$$$
Ive heard the fatties are actualy more prone to breaking than the smalls
Ive been looking at cats but the insurance is mind boggling ! And then theres the hairballs , litterbox etc ... LOL

An out board cat on Winni would be pretty stealthy, the tree huggers are more interested in those loud big blocks and wont even notice you.
I scan S&F once a day for lowers and they arent easy to come by at all. Im hoping the fishing guys will move to the 4 strokes and we will see more 300x's available for parts, we will see.
As far as the insurance goes I still think an outboard cat is still the less expensive way to run 100mph+ all day long.

Your right, its realy a noise issue around here. And there all convinced that two strokes are the cause of global warming