I’m not sure if this would help, but I’ve been talking to a guy who did design some LGB ones for a friend of his. He designs 1/43 British commercial vehicle of the 50’s. He is going to talk to his printer about making this…he’s admitted it might take a bit of time for anything to come back from this, but he thinks he can get them printed for under a tenner…+ post.
Here is a pic of one of his designs with some measurements. Looking at it, it’s not as rounded as the Bachmann front, but I reckon that by cutting, or even not printing the end panels, the screen would fit against the dash panel of the Bachmann tram. I think there would have to be a strip running in a curve just under the front of the roof to disguise the squareness of the screen, which would fit behind this strip and glueing on to the front of the roof.
As always, ideas and thoughts are very welcome.
Cheers
Martin