The trafos have a sort of similar pinout, use the mid-pin for ground and wire at will. I think the Lundahl was "reversed" with pins (2:1 step down) in compared to the OEP. I've got the G-Pultec board here on my hand, currently working on it and the Lundahl reminds me of the OEP on 1176 by it's pin layout. So what I think, you could put the OEP "backwards" on the PCB and rewire the mid-pin 3 with a jumper wire to it's appropriate place. Somebody correct me if I'm wrong? I don't know if you need an extra resistor somewhere, think this was the case with the 1176 mnats rev J board.