Recently serviced fuel pumps on each car. I noticed '79 450SL had a plastic sleeve around pump body at point where belly band bracket holds pump in mounting. The '72 280SE did not have this plastic wrap. Parts dept at local dealer didn't have one available and wasn't sure what it was for. My guess? Protection or isolation due to dissimilar metals. (Steel bracket, aluminum pump body). Anyone know for sure what this is for. I would like to install 10 mil plumbers tape if I can't find the plastic sleeve. Bosch supplier could not answer question. So, I appreciate any help on this. By the way, great forum!

Dana