I used 3m rubbing compound and a buffer. You cant tell that the original decals were back further after a polish. However, after being on for several years and a little fading, the old shadow appeared around where the original decals were. I buffed again with 3m compound and its gone again. Here is a current pick after this springs polish / waxing.
1999 sportstar 19, vortec TBI 310hp, acme 541 prop, 2006 prostar decals, alpine ida-x100m stereo, clarion speakers, kicker sub, and a JL XD600/6 amp.
stick of choice: 66" connelly concept. hey, im old school!