Ok, Let's assume that there are still people out that that like to slalom ski or at least would like to have a pair of combo skis with them on their boat. There are expensive and hard to find ski racks that are made to mount on towers. However, many towers have the standard finger rack that will hold both wake boards and surf boards. I have such a rack for my Skylon. But I'd like to get two slalom skis out of the floor of my boat. One night when I couldn't sleep, I started to think that the Y shaped racks that are used to mount guns onto 4-wheelers might be able to be repurposed for holding water skis. I let those thoughts marinade for a few months, and now that we have the 'Rona I went to Bass Pro Shop with my mask to do some shopping.
What I found greatly exceeded my expectations. I found a pair of multi-purpose clamps that could be used in a lot of ways. The manufacturer is Koplin Outdoors and the product is labled: Rhino Grip XLr [picture below] These Y shaped clamps are big enough to hold a water ski, they're rubber coated, and they have a stretchable rubber strap that closes the opening. They can be mounted to both flat surfaces and to rods / poles. In fact, You could use these to also fabricate ski holders under the gunnels where the combing pads are. You'd need to cut a rod to use as a mounting point.
I repurposed a cheap skim board that my son purchased years ago on a beach trip. This particular skim board cost roughly $30 and was pink. But the key was that it fit nicely into my wakeboard rack. In the pictures below, you'll see that the duct tape on the board gave me an indication of where the fingers from the rack were reside. The Rhino Grip Y shaped clamp lifts the ski high enough to get it over the board rack. Carefully, I measured out and managed to place two sets of Y clamps onto the board so that 2 slalom skis or a pair of combo skis will fit on this rack and then the entire structure will slide into a wakeboard rack. I hope my pictures below will tell the rest of the story. But if you have questions let me know.
If you're like me, the more items you can get out of the floor of the boat the better. Especially if you spend all day out of the lake and need to have all of your toys with you at the same time.