Bought a newish 18 this summer and found that the air intake on the hood needs attention on these sleds cause the fit and finish is not great. Mine had a finger width of room for snow and moisture to get into the air box. You’ll see this in the pictures below. I read a couple threads on kits you can buy to install before the throttle bodies but they were too expensive. I used materials I had in the shop including 3M Marine Silicone and 3/16 pop rivets. Filled the gap with silicone and then clamped it together. Installed 3 pop rivets in each side, then filled all the gaps with silicone and left it for 12 hours to set. Though I would share this idea and see what others are doing to fix this issue