Chris, A Forum member started a thread about how he started with an MTH mill and added an operating water wheel. You may be able to do something similar with the building portion only two inches deep.
Ameri-Towne, Atlas, Downtown Deco, DPM, IHC and Woodland Scenic kits have walls which could be use as flats or 2 inch deep building fronts(sides or backs).
John in Lansing, ILL