Re: Bare bones trailer mounted inline 6
The 300 was originally designed for stationary equipment, so you're on the right track. The more stuff you KEEP on it, the better & more reliably it'll run. At a minimum, it needs a radiator & fan, an alternator & water pump, a fuel line, a vacuum advance to the distributor, an ignition module with a START/RUN/OFF switch, a battery/starter relay/starter. If you wire it exactly like an older engine, it'll be fine.
That's not a 'vacuum plate'; it's the EGR valve, which should be left working, but it requires a few vacuum lines & wires that might already be cut out. Without it, the engine MIGHT run hotter, produce smelly exhaust, and wear out a little faster.