Evinrude 22 ci fastwin

hi. i new to the forum. was doing a lot of searching and digging around on some things dealing with this motor and yall seem to the best place for info on these motors. i have an 1971 Evinrude 18hp fastwin i got for cheap. it runs decent. im in the process of changing the head gasket and doing a carb rebuild. other than that the motor is in very good working order. its never been broke open. still had the paint on the bolt.
so i got a few questions for you guys. i am going to be putting a low water pickup and i plan on running the motor really high up.. im thinking about 1/2 the prop in the water. i do a lot of running in shallow water and want run this thing like a flats boat. there isnt much selection for these pin drive props, so would having a heavy cup put on the props i currently have for it help out? is there anything particular about these motors i should take into consideration before running it like a surface drive? im sure i will have more questions later on.