Due to water filling the lower expansion chamber the left barrel had corroded sticking the piston in place. With considerable patience and the application of gentle heat I managed to get the barrels off, not sure if they’ll be useable but that can wait for another day. Gear selector shaft is bent and had to be cut off so that I could split the crankcases. generally the rest of the engine is in fairly good condition.
The crank was stuck in the crankcase and required lots of soaking with oil to release it, had to tap a seal with a drift to get it the breakaway from the case. Complete rebuild of the crank will be done.