Andy,
I'd say just keep at it - patience and perseverance will win in the end. Keep dousing it with the Kroil, from the top end down.
I'd agree with loosening up the rocker arm assembly, since you're likely to have stuck valves, I would think.
Some people advise jacking up the rear end and turning a wheel with the transmission in low gear to turn the engine. Never done this though. This way or with a pry bar on the ring gear, take turns turning it both directions. The pressure both ways will eventually weaken the rust.
Personally, I'd want the tranny to be free, so I knew it wasn't the gearbox keeping the engine from turning. With the cover off the tranny, can you not get the shifter forks moving? Hear again, seems like having the rear wheels jacked off the ground would help.
Keep it up and don't lose faith. When you're ready to give up, let me know - I'll send a trailer for it. I've been wanting an Art Deco series commuter!
-Michael
