My 1983 MB240D has some windows issues that I am trying to resolve. Recently the RR window has been intermittent, hard to get to come back up if lowered. Now the LF is completely inoperative half way down and the RR won't respond to the switch either. I have cleaned the LF switch internally and continuity checking while operating indicates it is closing correctly. All the fuses in the main panel are OK. I have been told that perhaps there is a separate smaller fuse block with fuses just for windows and that the RR and LF share a fuse and the RF and LR share another one. I know from the electrical diagram that there is a window relay and it is of the multi-use "ice cube" type of which there are a few on the vehicle but I don't know the specific physical location of the window relay to check it out by swapping. Any suggestions would be appreciated.