pop rivets for 64 skylark convertible top boot


Hi. I just purchased a new top boot with clips for my 64 skylark. I need to pop-rivet the clip to the boot, but the instructions don't specify what size rivet to use. The diameter I can figure out from the hole size pretty easily, but I am not sure how long they need to be. Has anyone done this on a 64/65? What size did you use??