PopeDesign The bolster is offset so you can get the bolster pin in while the wheel sets are in place. FUD is not nearly as flexible or strong as injection molded ABS. So it would be really difficult to install the wheel sets after the truck is installed without breaking of the side frames off. I would suggest the one bellow in the attached jpeg. Its a simple bolster mount that would be a lot easier for you to design to than a male/female bolster setup like the coupler mount version. I also think it will be easier if I can get to my storage space and dig up some old N gauge stuff and grab a wheel set. Right now I'm in the middle of a fiberglass hood design project for an AG sprayer. So it might be a few weeks before I have some free time to tackle this. But this is something that can be done.
I found that even in just Z scale, no two wheel sets are alike from manufacture to manufacture. So there is no way I could guarantee N gauge wheel sets would work how they should or at all. Also I cant guarantee the truck bolster will match up and work with the N gauge body bolster. But if you want to take the chance, I can scale them up.
Have you looked at MTL deep well N scale cars? They do make one with buckeye 3 axle trucks and one with continental 3 axle trucks.
- Jon Pope
Well N scale is twice as big so that means I can model in a lot more detail... Honestly, its a matter of finding the time... And spending the money to make sure it prints... But some day I would like to expand into N gauge...