:fing32:Welcome aboard 1976dgs.
Getting it started and running should be job 1. Sitting for 5 yrs makes the fuel & fuel filter very suspect. It may not start on that old fuel but then again it may. Get a full 5 gal can of fresh diesel to take w/you.
The battery will probably be dead. It may or may not take a charge but I'd recommend to have a known good battery to start it up.
Check the oil & coolant before starting to make sure they're where they are supposed to be. Once it's started and running both will need changed. Condensation will have collected in the oil and rust etc., in the coolant.
Check the air filter. If it's clogged it'll probably not start or run properly.
If the fuel filter is a fuel bowl type, you should be able to drain it without letting air into the fuel system. There should be a fuel cutoff valve on it. Once it's turned on fuel should flow and fill it back up.
It may need the fuel system bled. IF so, you'll need a good battery.