Unsticking an unused engine........

273 Commando with 125K on a rebuild was parked in 1987 inside, but in an old laid stone basement, so it had humidity fluctuations. It was below the house in a drive out basement at ground level in Kansas City, but the temp was not well controlled (we fluctuate from -10 to +110 F over the years). No pipe freezing in the house, but still it has surface rust. I had last driven it in 1989, thoroughly brought it up to temp, reparked it, and drained the oil afterwards. I got it out a short while ago and am dealing with a stuck engine. I have pulled the plugs and used Marvel Mystery Oil, PB Blaster, WD40 Penetrant, and a mix of acetone and ATF. have filled the cylinders and it usually drains in few days or less. Tried to fire up starter and it engages but does not budge. I have been working on the crank bolt with a breaker bar and so far the only hint of movement has been tightening of the crank bolt. Don't want to break a ring (or the crank bolt, if that is even possible), so aside from patience and continuing to fill and refill with penetrant, etc.

Is there anything else to do? Heat, oil priming with drill and a shaft, percussion? I just want to do no harm, however. At some point I will throw in the towel and pull the engine to send off for the rebuild it is going to get anyway, but I would like to try to move the car from time to time under its own power.

Jeff-in-KC