You're definitely barking up the right tree. If your OVP fuse wasn't blown before (or even if it was) and it's the original that has only one ten amp fuse (see pic) then this is the likely culprit. ABS light is a giveaway too. Change it out and see what happens. If anything, you will
have to replace this part sometime during your car's life, either now or later. Part # for the bad batch of OVP's is 201 540 38 45.
'91 300E, 215K miles