What are the sizes of some of these trains?

I've been wondering what the exact dimensions are of a generic chassis of a Thomas & Friends engine, rolling stock, and unmotorized character. I also would love to know the dimensions of a Capsule Plarail, since I'm planning on using a Capsule Plarail Henrietta's face on my Plarail Henrietta, but I don't want it to be too small or too hard to apply.
I'd also love to know since I don't think I own a measuring tool that measures millimeters, which is what I'd prefer so I can get a perfect match or near-perfect match when making some custom models to 3D print.