There are a few tricks. First, I use a little piece of scotch tape on the back of the rivet to hold the shaft in so that it doesn't fall through the rivet and into the beam. Usually when that happens, it is on the second squeeze, so you end up having to drill the rivet back out again. You need to use stainless countersunk rivets and they run about a buck each.

I have one of those industrial rivet pullers that has long handles and looks like bolt cutters. You can get them on eBay at a great price and I really recommend them if you are dealing with stainless rivets. I took the head and ground off two sides so that it fits into the traveler track and sits flat on top of the rivet on the bottom of the track. Works like a charm.

Also, when using stainless, don't be in a hurry to aqueeze it. You end up poping the rivet too soon and it doesn't set well. The best way is to slowly but firmly squeeze it and get as many pulls as you can.

Man, that sounds perverted, but I'm talking boat parts!