I'd say there is a good chance of it fitting... the tunnel width is the same as the PRO-RIDE sleds... and I suspect the splines for the QD are the same as well.
However... I would count on it costing over $500 plus shipping, with a discount.
Also note that it would be a steel shaft from the 2016 and not the aluminum one.
Plus... you will most likely not be able to get your hands on the 2016 AXYS part until November or so. (just a hunch)
IMO... finding a good used steel 2011-2015 RMK/Assault/PRO shaft OR ... a 2005 900 RMK shaft and using the AVID 7 tooth, 3" pitch, "Power Claw Style" drivers will be a superior setup to the stock setup... the only drawback is that you would have to trim the rail tips. OR... Robbie at AVID makes a very nice center driver 7 tooth option so that you do not need to trim rails, or swap shafts... that option IS available for the steel OR the aluminum shafts.
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