Make your own tool with $2 worth of hardware store parts:
[img]http://www.bermudaschwartz.com/images/gromtool2.jpg[/img]
First, straighten the badge and tape its edges to the shell so it doesn't move.
Hex bolt goes from inside of drum through the grommet, 2 nylon washers go over end of bolt against the badge side of the grommet, and the nut goes on after that.
With a hex wrench, 'hold' the bolt in place while you turn/tighten the nut with a wrench. You won't need much pressure to make it tight, and over-tightening may flatten the rounded side of the grommet a bit.
Sorry, I forget the sizes on the parts, but you can simply measure the grommet hole and go a little smaller with the bolt size.
Good luck!
Bermuda
Here's a better example (without a grommet) and using one rubber washer, but I'd say stick with 2 nylons...
[img]http://www.bermudaschwartz.com/images/gromtool.jpg[/img]