There is a method but it is painfully slow but does not involve large amounts of brute force. You will need to obtain a good quality guitar steel "E" string and a couple of heavy weights. Support the stock and action on a table with the but plate just protruding and in your case toe up. Next put the guitar string in the gap between the stock and the plate, then hang your heavy weights on each end of the string so they are applying a permanent downward force. Then heat the but plate with a hair dryer as hot as you can safely go, with the heat and weights on the wire guitar string, it will slowly cut through the glued joint. It is not fast but it will work given time.
