I am starting a project - Atkin-style tunnel stern, of welded aluminum.

I have been offered a Datsun pick-up truck with (I think) an SD22 diesel -
widely used in forklifts, IH Scouts, and some boats. The truck has been
immobile for a few years, but ran ok when it was parked. I have no
experience with diesels.

Questions: Is there a recommended procedure for starting such an engine, and
checking it over? If it's not in reasonable shape, I would want to know
ASAP.

Any concerns or suggestions for dropping the engine into a boat? Cooling
would be fresh-water, through a "keel cooler" integral to the aluminum hull;
exhaust (wet or dry) to be determined. Could auto-style vibration mounts be
used? I know I need to check on regs for fuel and electrical systems.

Transmission - it seems simple (and cheap) to use the 5 speed transmission,
with driveshaft attached to prop shaft with CV-joint and thrust bearing.
This would allow some variation in reduction ratio, for varying conditions.
Am I nuts?

For prop sizing and the like, I am assuming 40hp at 3200rpm (intermittent-
or heavy-duty operation; a few hours at a stretch). Is this reasonable for
this engine?

Any suggestions? good info/resources?

Thanks - Sal's Dad