I visit 1 yard with many scrap/ not worth fixing boats.------But I know there are many folks who think.---" it is fiberglass , nothing can be wrong "-----Little do they know of the junk wood in them.----Or shoddy work under the floor !
What you are seeing is all normal for that 2 stroke motor.----The hole is put in to drain the casting cavity.----The leaking oil is the oil you mix with the gasoline !!
Clean the carburetors-----Find / clean the high speed jets screwed into the bottom of the float bowl.----Do not run this motor , as plugged carburetors can result in major damage to the motor.
For many folks ,big boats become a liability at one point.----Too big to trailer.----Too expensive to repair.----No insurance available.----Too expensive to dock for a season.----Nobody wants them.
The first step in trouble shooting these crossflow motors is a compression test.----Post the actual values you get.----Fuel pumps are operated by crankcase PRESSURE and not vacuum.