That is the right way but if you ever have to remove the splitter= new rivets. PITA! I use Phillips screws with a clip nut.
The center pin is aluminum. Easy to remove with a small drill bit or a hammer and chisel (screwdriver) works too.
I got an air powered rivet gun from HF for $50 that I keep in the shop and a manual gun that I keep in the trailer.
The 1/4 inch rivets also work great for attaching ACR-X canards as well as rear diffuser fins. I'm tempted to use them to attach the
botton side of side sills as well as the fender skirts to fenders. Those "Loctite'd" screws seem to disappear.
I think Summit has the rivets in various colors too...