I made a front plate bracket out of a scrap of carbon fiber composite I had lying around, but aluminum would work just as well. The goal was not to drill any new holes, so this uses the two lower bolts that hold the grill screen in place. We have a once a year inspection in Massachusetts and they check for a front plate. My thinking was I would take it off every year after inspection, but I ended up leaving it on all summer.
The bottom line is there is no good or attractive place to put a license plate on the front of a Europa. I hope you will take this with the humor that is intended Sandyman, but the first thing I thought of when I saw your under-the-bumper plate was a bucktooth cartoon beaver, or maybe "Mater" from the Pixar "Cars" movies.
Tom