OK, I got the call from Rovers North. They tested it against other frames and other bumpers and they measure 7/16th of an inch too wide. They even called a few other customers to see what they had come across, confirming what my issue was. I was the only one to whine about it! LOL!
So they recommend just using spacers. I'm not sure how I feel about it, but with the two bolts through the frame at the back, plus the four main bolts, I also can't figure how it could be a "bad" thing.
I asked about the steering guard issue, and he did say that the steering guard needs to be modified. I tried it, but there is still not enough clearance to get the skid plate mounted. Some other bracket will need to be welded up, and a new hole drilled in my skid plate to make it work.
However, they did come through for me in the end! Took a while, but actually ended up lining up exactly with when I got the truck officially back on the road anyway. So I'm off to the DMV!