We started that a few years ago to try and help out assembly. Tapping and threading takes a lot of effort, these help keep that cost down.
Joe
tapping and threading takes a lot of work for the modeler, too. If I could just pop a 00-90 plastic pin through the box into a 00-90 hole I drilled in the car frame I'd find that preferable to diddling around with tweezers and jewelers' screwdriver to get the screw in. Any chance those pins might be in the coupler kits someday, w or w/o the screws? As for coupler box swing I thought that cure was provided years ago with a dab of Goo at the end of the inboard end of box?
This was my first undec MTL heavyweight so I never examined the pins b4.