To powder coat, doesn't the tunnel have to be taken off the sled?
If so, sounds like a lot of effort to me.
To prevent snow/ice buildup on the running boards, I cut a two pieces of flat plastic sled material and zip tied to the top of each board with 5 zips down the middle or so. One swipe with my foot and the snow is gone just like that.
Traction on the board - there are a few times when my foot is 100% on the plastic and there is less traction but for the most part my size 13 boot is partly on the serrated edge of the board anyhow.
The plastic does provide more traction than snow/ice which usually tend to let your foot slip over the edge of the board anyhow. With plastic, at least there is still a lip on the edge to hold your boot in place.
My $.02.