mercury tower of power 115hp rebuilding

[simn20]

hi all,

my 1981 mercury ouboard inline 6 115hhp as start to grip on cylinder 1 and 2. i dont know what cause it overheat or a weak carb. the engine still run smooth at idle, and start like a charm

now i wonder if it worth the rebuilding. im probably gonna have to oversize the engine and change the piston. its a 900$ for the rebuilding kit including wiseco piston + 250$ for the oversize + time to rebuild ( i dont do it myself, anyone know how long i can think of, for removing the powerhead from the outboard unit to complete rebuild includind carb and fuel pump?).

i found already rebuilded powerhead fo 1500$ + 300$ shipping at southwest marine in Fort Myers, FL. anyone know these one?

what you think does it even worth to spend time and money to this unit?

your comments are welcome