Dental floss is what my very knowledgeable detailer told me to use if I ever wanted to pull the badges off. And since that's what he does on the Ferrari's and such he works on I'm sure it'll work fine on our BMW's.
You'll need to hit the area with some 3M adhesive remover or Naptha (Zippo lighter fluid). Then immediately clean/wash the area.
I'm sure you'll need to give the trunk a good polish. Black E34's usually fade a little and it doesn't fade under the badge. Can usually be made to be virtually invisible with a good polish & wax job.
Cosmos Black/Black 1995 540iA M-Sport
BMW Individual Exclusive Edition, 1 of 65 total, 9/25/95 Build