Rear driver side and front passenger side window
 

Initially none of the window work, I thought it was the switch since all but one of the switch on this car were broken. So I took the known good switch from the 1985 300SD. Now the front driver side and rear passenger side work, I understand these are on the same fuse as the front passenger and rear driver side.

I did a quick test light on all the fuse, got dark so I did not take a photo on which fuse were dead during my reading.

There are two fuses for windows on a 123. Fb and Fc. They feed the windows as shown below.
Excuse the crude graphics I'm typing this on an iPad.

--hood--

Fb...... Fc

Fc...... Fb

--trunk--

There are a couple things to try
- stuck window regulator blew the fuse
- frequent flexing of wire pack in door hinge area (the rears seem to be worse about this) causes wires to break and or short.