Tomcata3,
I have an M35A3 and have been driving it for about a year. I have a flasher that works intermittently. Sometimes it works normally, other times the Green light comes on in the cab and stays on. When that happens the lights outside don't illuminate at all.
I took my flasher off and sanded all of the ground points so it would make better contact. When I put it back on it did not improve the situation. I think temperature affects it's operation. More heat, less reliability. But, I'm not sure.
Anyway, to answer your question, the flasher on the M35A3, is located on the left fender, inside the engine compartment.
A new one is about $47.00.
Hope this helps. I need to get mine working also.
Freight Dog