Skip, I attacked the seam with a wire wheel on a die grinder first. I dug around a bit with a thin screwdriver but that wasn't getting it all. I chucked a thin cutoff wheel in the die grinder and ran it down in the seam to grind out all of the buried rust and old crusty seam sealer. You've got to be careful doing this though. The cutoff wheel will cut into the metal if you let it. Once it was clean and all blown out with air, I cleaned it with acetone and brushed in POR15 to stop whatever rust may be lurking below that I couldn't find. POR15 doesn't like to be painted over, so I used another POR product called Tie Coat which is a primer that will adhere to the POR15. Once that was dry, I filled the divots left by the rust with 3M body filler and sanded smooth and primed with spray primer. Applying the seam sealer was the last step before paint. The sealer comes in a tube like caulk. I just ran it across the seam, making sure it got forced down into the void. Wait 30 minutes and spray away. It was a time consuming process to say the least.
I am fortunate to have two great children to make memories with. Nathan's sister, Ava is 7 y/o. She loves the old cruisers as well but her affection is more along the lines of being "normal." She likes to ride in them and she thinks they look cool. Nathan, on the other hand, is completely obsessed. The apple doesn't fall far from the tree I guess.....