A bit of an update:
Bumper progress has been slow. Got the main part finished up... I think. Just have the receiver and sides to do now, hoping to get those done relatively soon.
In other news, since installing the wheel spacers, I've had a lot of rubbing. I've tried to cut and cut, which I thought solved it, but it rubbed again today and now I'm stumped on how I can solve this.
Now, it's not a super big issue, as it only rubs at a very specific angle. It's near full lock, and the axle has to be flexed somehow- generally a bump on a turn can do it.
Trimmed:

No, it's not the prettiest, but it does the job. I went back and cleaned it up later, so it is a bit nicer than pictured.
Where it's rubbing now:

Any ideas?