That's a WPC voltage plug, like in Doctor Who. ToM is WPC-S, the larger 12-pin connector.
If you remove the voltage plug, and put the tab to remove it pointing down, pin #1 is the upper left corner
For 240 volt operation, you need 3 jumpers
Pin 1 to pin 11
Pin 3 to pin 9
Pin 7 to pin 10
Properly repaired, as Beaky stated, the GI in your TOM should be good for YEARS of trouble-free use, especially in the home. There's something else wrong, and it's going to smoke a replacement board. Get another tech.