Hi Herb, I don't have updated numbers - just the original number from the parts catalog - do you need that? And what's your serial # in case there's a break

I'm planning to put D3 rollers on my 5U, including the carrier rollers. The D3 carrier is the roller and a plain round shaft stub that sticks out and is clamped into the carrier stand on the D3. I think that means I need to adapt the top half of the D3 stand to fit my D2 track frames. I might just even make a stand out of some thick wall tube and a plate. The clamp should just be a tube sliced down the side with a bolt hole "attached". Not sure if that's anywhere near what you're doing?

Looks like I can add the cab attachment to my 5U now with a/c and a radio : )