[High Wire]

Lots to consider

Mechanical:
Where will it fit?
What has to be moved?
It’s going to weigh around 350-400 pounds. How will that affect the boat trim?
Where will the exhaust go?
Cooling water seacock and strainer placement.
Access for maintenance.
Fuel supply,, filter and return lines

Electrical:
Kw? Depends on what loads you have. Electric or propane stove? Air conditioning? After about an hour of running the loads drop off and start cycling. It’s generally bad to run a diesel long at low loads.
120 only or 120/240 VAC. Depends how your system is setup.
Inverter/charger connection
Transfer switches
Starter battery location