Long story, but due to a broken bleed nipple I had to remove the rear subframe and get the calipers rebuilt. Got that done, cleaned everything up and refitted the subframe. However, I didn’t drain the oil and forgot to undo the inspection/filler plug while it was apart. I now need to top it up and while the drain plug is OK, the filler plug has been well rounded over. I can try mole grips etc, but it looks like that was done last time it was off and, having tried a decent spanner on it, the metal seems to have turned to cheese. One other option would be to remove the end cover of the diff (I have a spare gasket) and remove the plug on the bench.
So, does anyone know if the cover will come off with the subframe in situ? All the bolts seem accessible, but not sure if it will clear the edges of the subframe or maybe go out sideways. Would appreciate it if anyone has ever done this! I am really not looking forward to taking the subframe off again!