First question would be if it turns over by hand or is seized up. If it's seized then your buddy is probably right, otherwise, get it running and see what ya got.

A little light oil sprayed down into the cylinders through the spark plug holes would be a good thing to start with either way. As for the oil in the crankcase, yeah, good idea to drain it, but just putting new in without some aggitation/circulation won't do much. Don't believe any stories folks might tell you about "detergent" oil loosening up any sludge, the "detergent" in oils is really a dispersant that's intended to keep particles suspended when produced. What loosens up the existing deposited/sludgy material is flow. Some will recommend putting in some diesel fuel (or kerosene) to loosen up the sludge, but again, works better when agitated.

As for the cooling system looks like that sludged up too, only likely from old antifreeze. One thing you can do is to cap those lower outlets, pour in some baking soda through the upper hose necks (take out the thermostats), and follow that with some vinegar (just regular white is fine unless you're a gourmet and insist on red wine or basalmic ). The combination of the acid (vinegar) and the base (baking soda) will make a bubbling, churning solution that will loosen up sludgey, slimy stuff (works good in sink drains too). Then you can drain that off and follow that with a blast from the garden hose. Yeah, you'll get really wet, so do it somewhere where you won't leave stains and the water will run off. If it's antifreeze sludge, make sure no pets are around to drink any of the runoff.

To get it running you'll want to check all the ignition components to make sure they'll work; wiring, points, rotor, condenser, coil, and plugs. You may get away with the carb, though it's likely gummed up and will need some cleaning of the jets and needle/seat. As Don suggested earlier you can run it off a gas can, just hook up a long enough hose to the fuel pump inlet to suck from the can. Probably should check to see if the coil is a six or twelve volt. If it's 12 then use a 12v batt, the starter doesn't care. If it's 6 then you need to find a 6v batt or start your upgrade to 12v.

Some "good" news, it looks like it's a Mercury engine rather than a Ford. Not a lot of difference except the Merc has more cubes and hp, and has more appeal because of it.