Oh yes, and another thing. Get the DRDT dimpling tool from Paul Merems.
Paul is building an RV and has designed a really nice (SILENT) dimpling tool. It is large and realtively expensive, but really a slick machine and worthy of the slightly higher cost. You won't need the Avery "Smash" dimpler if you buy this one.
Paul's site is
www.experimentalaero.com and on those pages you will find info on buying and or building the DRDT. I welded my own DRDT together and purchased the plans and "Front End Kit" from Paul. Paul accepts Paypal, so I sold a bunch of stuff on ebay first and paid Paul with that money. The steel, well I found some scraps for free. All I had to "pay" for was paint and dies.
I will take a picture of my DRDT. Paul had asked me for one a while ago and I failed to send it, so it is about time I do so.
Look into it. You will be pleased.

CJ