Your basically trying to get the head of the rivet off the shaft in order to remove it. Once the head's off, you can usually push the shaft into the hole and you're done. Drilling is one method, as Silverhobby mentions. If you can get under the rivet head, you can dislodge the head (think hitting it from the side with a scrapper blade wacked with a hammer).
There is a tool (isn't there always
) and since you mentioned it, I'll tell you about it. I found about this from another poster here on the AirForums...source of all aluminum knowhow! It's available from Aircraft Spruce, who you'll find is an invaluable source of supplies and tools for dealing with rivets and aluminum! Here's the
link.
AND, I'm in Central Indiana, and would be thrilled to meetup with other Airstream buffs! So let's do it!!