rebuild vs New motor

[wildtalk]

As soon as my F250 Ford Truck is paid off I want to get the motor part of my boat in order.. Are 4 strokes a LOT heavier then 2 strokes..in other words,,,is it best to do a complete rebuild on the old 1987 Fast Strike 2 stroke smokie due to less weight OR ,, or spend the bucks for the purrrr of a 4troke maybe a lot heavier ?? 20 foot vstep Wellcraft,, waiting on your advice as what she will become. Thank you