So I picked up a 2015 Skandic WT 600 ACE.
I realize the 2015 Skandics kept the old style DESS key. From what I can glean, upgrading to an HF key would require a new HF style post and a new HF compatible ECM. Wiring harness appears to work with either key style.
Ive never run a sled with the old style DESS key. The one older Skandic in our group has the old key. Never really had an issue, although once it a while it does need a wiggle.
I was thinking of just replying the old DESS post with a new "old style", get a replacement key, and install it with a bit of dielectric grease on the contacts and a bead of silicone around the rubber just to make it more or less permanent.