I will be installing a 153" 2.6" powerclaw on my XF7000. The 141" Viper/XF7000 use the same part # 3" pitch 8 tooth drivers as the Proclimb mountain sleds, which run the 2.6" powerclaw.
I checked them out at a sneak peak earlier this year and it looks like that they should fit.
My sled is in route to the dealer as I type this, so hopefully I should know for sure soon!
Bill