Unfortunately, even sticking to the same engine manufacturer/marinizer can necessitate the same upgrades/updates as the base model of the engine in the used will have changed since the model in the boat. The marinizer of the engine has littlle to no influence on the position of some of the engine controls and services, even Yanmar had changes to which side the heat exchanger and exhaust was on the change from the GM Series to it's replacement, the YM series.
Originally Posted by OldColumbia
The problem changing engine manufacturers is the different dimensions, shaft length, prop size, and hose placement. etc. Our last repower evolved into relocating the hot water heater, new motor mounts, new shaft ( shorter), cutlass bearing ( the shaft was out anyway), relocating coolant tanks, and replacing control cables because of change in throttle location and transmission shift lever.
Each costing more in parts and labor. I'd keep it simple with a like kind engine.