Never got into the Hydra-Matic, if one had a later open drive shaft model, could the tail piece be swapped from one of these to make it for an enclosed driveshaft? My 1956 Pontiac still has the older version of the Hydra-matic without the park.
So far I haven't had much luck in finding a 53-54 Powerglide yet. Seen a '52 model and engine, but they weren't self shifting and the torque converter was redesigned for more efficiency in 1953.
John