My K-27 arrived this afternoon--and the second thing I did was install Kadee couplers. Here's how:
Tender is a drop-in fit of a #830. Right on the money for height using the Bachmann pocket.
Spoke pilots are a bit harder, as the mount is higher. The #830 fits, but is high. It needs about a 1/8" shim between the top of the pocket and the coupler box--perhaps use the box lids that you don't use with the Kadee 830's. The uncoupling pin must either be cut off or bent to clear the pilot.
The plow pilot is going to be another project entirely--but I understand that John Sipple from Model Railroad News is bringing a #464 with plow for Sam to puzzle out.
GJ