Here's what I've used (from a previous thread on carpet removal) .... https://rennlist.com/forums/928-foru...l#post11939643

Draping the area with rags wetted in the solvent for a while limits the quantity of solvent used, and keeps the area soaked for long enough to really soften the glue, for easier removal with scrapers and solvent soaked rags.

 

Thanks Dave!

Will try to find that kind of solvent. Will probably be usefull inside the car to.

 

A heat gun on the bitumen floor sound deadener works for initial removal, followed by that solvent, which I've used successfully on all the internal surfaces. If you really want to get aggressive you can use Acetone, but be aware that it will soften/remove paint, so just a quick wipe in stubborn areas can be useful for final finish off, and is a good preparation for re-painting.