Sleeve, Chrome, Shower Faucet: Won't Come Off

How in great blazes do you remove the chrome sleeve off a shower (hot water) faucet that doesn't want to come off? (to access the stem to change a washer.)

I tried turning if off with a channel lock / vice grips and just succeeded in scraping the chrome off the brass and changing it from round to oval.

I'm thinking a rubber strap type wrench might work. I've never seen one though.

sleeve

IF it is the tubular sleeve screwed onto the outside of the faucet stem, find a socket that just fits inside it, (usually about a 13/16" x 1/2" drive), place it inside the sleeve and then grasp the sleeve with the pliers and remove it. The socket will keep the sleeve from distorting and locking onto the threads.