As you are doing, you can't do that directly because you can burn the horizontal transistor while it is good, compare the flap of the 14p TV with that of 21p, compare pin to pin if they match the same, I think maybe you can change the flaybag and the Capacitors tuning in, analyze the two cards around the flaybag to see that there are more different ones taking into account the reference of the capacitors of both cards