Don 't forget the 2-Railers...

[DominicMazoch]

I do 3R O.  But I think 2R is possible.

The motors on the locomotive are already DC, the current bing rectified by the E unit. 

So:

1.  Take the E unit and horn out.

2.  Place a DCC board or at least a socket in.

3.  Scale wheels and 2R pick up.

Maybe you could offer it in the future as a "pre-order" item through your dealership.  Then if there is enough product on order, you could make it without losing your shirts.