"freelance" 1:20.3 passenger "varnish"

This is my first my attempt to bash some freelance 1:20.3 passenger "varnish."
I needed some passenger cars for my narrow gauge, turn-of-the-century D&RGW Rail Road (the Dulles & Reston Garden Weeds R.R. - not to be confused with that other D&RGW Rail Road.) But those beautiful San Juan cars that Accucraft makes are just too heavy and long, not to mention, for me to expensive.
So I took some 1:29 scale USA Trains Overton coaches that I already had, added about a half inch to the sides and doors, some brake beams to the trucks and, of course, repainted and relettered them (with Stan Cedarleaf's help.) I know they look kinda like the "Toonerville Trolly" but I couldn't figure a way to make these any wider, just taller.


They started out looking like this:


Here's the whole train


The combine


The coach


The observation car


The other side of the combine


... and Ken, the traveling salesman, contemplating sales prospects in the next town from the rear platform.

How I did them...
I wish now that I had taken photos of my bashing. The best I can do now is describe the process.
The car bodies (the sides and floor) are a single casting. After removing the roof, interior details, windowglass, underframe and trucks, and laying it on its side, I made a horizontal cut just below the windows (after removing the trim piece) using a bandsaw with a rip fence. The upper and lower pieces were rejoined with plain styrene filler strips, about a half inch high, glued flush with the outer surface of the siding. I then used the gaps in the existing siding as a guide for my razor saw to extend the gaps up into the filler strips. Two or three passes were all that was needed for each.
The upper joint was concealed by horizontal trim below the windows and the lower joint was filled with Squadron "Green Stuff" and sanded smooth. I had to recut the gaps in the "Green Stuff" to rescribe the lines in the siding after sanding. I also used strip styrene to fill in the trim around all the doors.
The end doors on the platforms and the two sliding doors on the combine were extended essentially the same way. I used a miter box and a razor saw to cut the doors in two, horizontally. The combine doors were cut just below the horizontal trim piece under the windows and the end doors, which were simple two-panel affairs (the upper panel being a sheet of "glass" - actually clear styrene,) were cut at a point on the lower panel where one joint could be hidden under a crossbar making it a three-panel door.
An insert of plain sheet styrene, matching the thickness of the "base" of the door was cut to the right height and the same width as the door. Laying all three pieces flat on my work surface, I glued the insert between the two original pieces of the door. When that was dry, I cut strip styrene that was the same width and thickness as the raised trim pieces on the door and glued them vertically on either side, and in the middle in the case of the combine doors, and butted them to the existing trim. On the end doors, I applied the same type of strip styrene as a horizontal crossbar over one of the joints, creating two equal sized panels below the window. The other joint was filled with "Green Stuff" filler and sanded smooth, as were all the butt joints in the trim.
Finally, the doorknob, which I had carefully removed at the base with an X-acto knife was glued back on a little higher up at the correct 1:20.3 height.
It's a very simple process, really. The key is to make sharp, clean cuts and use filler, sanded smooth, to conceal the joints under the paint. Hope this helps.
Until somebody (are you listening AMS?) comes out with some affordable plastic open-platform passenger cars, these will have to do.