Mercedes in Germany and I believe from the USA are available debadged as a factory option.
If you are like me you ask the dealer to take their sticker off.
One of the reasons you may wish to do this is for the lines. While the original Mercedes lettering is beautiful. Something like CLS 63s 4Matic can be a lot for the back of a trunk lid. Additionally, the CLS 63S isn't available right now -- it can date your car. Mercedes ownership to me isn't always about novelty it is about quality.
I believe a good Mercedes is worth holding on to.
I would caution about debadging a very old car if it has spent most of its life outside as the paint difference may go beyond hand polishing/compound application.
In general you can use a heat gun, apply it to the letters. Use a nice taped flat scraper like you would use for a 3D printer or floss. The idea here is to not touch the metal at all, or extremely minimally with the force against the letter and adhesive.
This makes it slightly harder to clean up but provides a margin of error. I would also proceed slowly around the adhesive in a controlled manner. This is not the time for proverbial sledge hammer, it is easier than you may imagine and if it isn't stop.
As with anything on this page it is just a blog about tuned Mercedes. We are not advocating anything (although removing resonators and adding air intake spacers from UPD is really close), it is up to you. All damage is yours. Please proceed with caution, get the latest info from STAR or some place like this http://mbepc.net/ do not proceed, reach out on MBForum talk to an expert like K. and go step by step if you are a new kid on the block.
After you have debadged you may want to consider cleaning up with a soft microfiber and some 70% alcohol. After residue has been removed it is time to use a bit of rubbing compound with a soft terry cloth. Although the pro's on youtube use the 3M Eraser tool to debdadge their car and some sort of tool I have never considered buying, perhaps it is just a normal rotary?