Tim, If I've seen your page before it's been a while. Great resource and thanks for sharing.
I'll give the engine a good going over. Hopefully it's not rust locked. Since the oil fill cap is off the valve cover will need to pull the cover and check for dirt dabber mud houses along with mice dens. Then if it spins and since the starter is still on the bell housing I'm thinking it should be pretty easy to pull the plugs and do a quick compression test. Assuming the owner will allow. If it passes those checks it's coming home with me. Obviously I need to know if it's a 235 or 261 and will figure out those details later.