Does anyone know if a waterpump for a 102.985 engine will fit on a 102.961 engine?

84 is the only 190e 2.3 with the 961 engine however the 985 engine is on '85-'93 engines. That gives me a lot more options finding a compatible part for my '84 at the wrecking yards.

I need to replace the electro-magnet for the main radiator fan because i broke the plug off. They're pretty hard to find cheap. I'm thinking if i can change styles of water pumps i can change styles of the magnet and the fan should still mount the same.