batman wrote on 03/20/17 at 11:48:28:If all else fails drill a hole through the center of the plug ,using a proper size drill bit ,tape the hole using a pipe tap,as they make a tapered thread(and should be easier to start in a slightly undersize hole) using a 1/4 or 3/8 tap .then all you need is a pipe plug and a roll of Teflon tape.Apply tape to the plug as a sealant and to be sure your plug will never seize again.
I don't think you can drill the drain plug with the engine in the frame......the frame is in the way.