R:

Your quote:
I tried disconnecting the battery + while the car was running and although the idle dropped for about a second, it was OK.
I had to have my jumper car run for about 10 minutes to get the Merc to start. As soon as I shut it off, it wouldn't start back up again.
Any thoughts?

1) The battery disconnection while running caused a large voltage spike system-wide. It is quite likely that some of the more sensitive electrical components of the car have been damaged by the spike. The OVP relay affords some protection, but was not designed for this case. The ECU and the EZL are possible victims, as is the fuel pump relay, and the ABS controller.

2) Try reducing the size of your pics; the post is very wide as a result of the oversize pics.