I think the correct terminology is early kit, there were no 818 beta builds

Erik what is your serial #? mine is 17 and I'll be tweaking, mine look like your's. I think one issue is the 5/8 measurement for the sides/rear fenders. That measurement is made after riveting an aluminum panel over the frame. When you piece together 8 major 3D body panels to control gaps there is some variability that results, it doesn't take much for the gaps to look "off"

Look at the issues some are having in the front. Between rear bushing mounts that are off, early steering rack mounts being off center, any misalignment of the holes through the brackets can cause you to twist and distort the rubber bushings a bit. It all results in slightly differnt wheel positions.

I think that long term it is the nature of the beast. We would be well served however if FFR could give us some hard and fast measurements so that we could work them while building it up vs after everything is mounted and the body is on casuing us to redo everything.

I've done some browsing on the forum of other FFR models and every model has similar issues. So... many... variables...