Gotta have both valves closed tight. There's about a 1 in 6 chance of that happening, and even then a slightly sticky valve would keep pressure from building up in the cylinder. If he has one of the "Cheetah" tubeless tire inflators, it might be possible to hit the cylinder with a quick shot of compressed air with a little creative plumbing, but that's not something most guys have around a farm shop.

http://www.northerntool.com/images/product/400x400/121/121488_400x400.jpg

One possibility would be to fill a cylinder with oil, remove the pushrods or at least back off the valve adjustments, and use one of the Porto-Power jack power units to pressurize the cylinder. Even then, it would be a crapshoot to pick which piston was actually stuck.

I've got a 307 V8 in a 59 Burb stashed out behind the barn that hasn't run since the mid-1990's. It's one of those IRWIPI situations. Just for grins, I might try a few of the techniques we've discussed here when I pull the engine, assuming it's stuck (which it probably will be).
Jerry



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