For installing the MT couplers, I don't remember who exactly on the N scale forums recommended using the MT 1163 pilot
coupler adapter, but found that it fits well, and by putting one of the MT shims above the MT 1015, that the
coupler sits at the correct height.

Yes, I needed to cut the lower edges out of the RSD-15 shell. Maybe I will be able to better blend them in later, but for right now,
the goal was to get easy-to-install, correct height, strong adapter.

Note that I chose to mount the adapter inset back a little from the front edge of the end face.
This is because I needed to drill the coupler screw mounting hole into strong thick plastic area, not in a
thin area. The result is a good enough in my opinion.