Well I'm stuck - literally. I removed the radiator to get it pressure tested and cleaned, and actually, I'm very impressed with the condition of the radiator - the fins look great, there doesn't appear to be any signs of former leaks, and there doesn't appear to be any cracking. With the exception of some dents on the backside and a few dented fins where the fan blade touched, you'd swear it was a new radiator.

So, we were off to a great start, and with the radiator out of the way, I thought I'd put a 1-5/8" socket on the crank nut and try to turn the engine over... No luck whatsoever.  It is tighter than... Well, you can insert your own phrase.  I then removed the starter and generator to see if they might be hanging things up, but no dice.  My father-in-law, Norm, had a great idea and suggested pouring in some Marvel Mystery oil in the cylinders, so that's what I did today.  I also pulled the valve cover off and poured some over the valve train.  So we'll let the oil soak for the next seven days and try to turn the engine again.

I'll keep you posted.

(You can click on the photos to view higher resolution versions).