Here are some photos of the fusible links in my '89 525i.
My car has an m20 engine and the battery is located in the engine compartment. (and the driver sits on the left)
There is an 80 amp fuse located near the passenger side front shock tower.
It broke when I moved it a tiny bit, all of a sudden the car was completely dead, in the rain at night. Easy fix, though.
There is a 50 amp fuse under the rear seat, near the connector (which can also break).
Mine looked to be in good shape but I replaced it anyway.
There are some good pics of a fusible link in an e32 here. I believe most e34s have the battery under the rear seat (where my cd changer is), so the location is probably a little different, but it's there, somewhere!