Some updates.. I figured out a pretty easy way to centerline small round pieces. Just put a grid paper under it! The bigger wheel, with six holes, is for the front/tension wheel. I just drilled 10mm holes and used a
thing like this to make the shape. What is that called in english? Anyway, I've made two of them. I hope that last two will come out a little better so I will put them on the more visible outer side
I tightened a bolt to a bearing and place it in the bearing house so I can align the housing while I tack it in place.
Also figured out a stupid easy and simple way to mount the suspension rods.
Btw, spring steel wire at Finnish scale model shop = 30 euros per meter. Price at local hardware store = 30 euros per KILO! A little cheaper

And they gave me a bunch of different diameters for free to measure what I need. 4 or 4,5mm feels good but I'm starting to think my estimation of 40-50kg is not enough for the complete model..