Shrinking Disc
In the video I demonstrate using a shrinking disc, by removing two dents in a domed panel.  Once I got the dents shrunk back down (I did
NOT use a hammer and dolly, only the shrinking disc for demonstration purposes), I ran a DA air sander over the panel to show exactly
how smooth of a finish can be achieved.  You could never tell there used to be dents there.

In normal conditions, you would tap the dents and low areas up with a hammer and dolly, make a pass with the shrinking disc, and tap up
any remaining low spots before making another pass.  After a few passes your panel with be smooth, and back to normal surface tension.
This is a YouTube video, if you prefer to watch a MPEG or WMV not on youtube, the same
video is available in both those formats as well.
MPEG and WMV Video Formats
New High Definition Repair Video on a 1941 Lincoln Continental!