I live in British Columbia (BC), so I needed a license plate adapter for an Italian to standard North American plate for my 1973 Autobianchi Giardiniera. I was using zip ties, but that looked unacceptable. I scoured the Internet, but I couldn’t find an adapter. It was bugging me, so I created one using FreeCAD and our 3D printer. It works for my car, but I based it on information I found in general for Italian license plates as well.
A BC plate is about 12 inches wide (304.8mm) so the holder I created is 307mm wide. Since I have a Creality CR-10 3D printer with a max bed size of 300mm, I split it into two sets of files; one set small enough for 3D printers like mine (it has a main piece and side pieces that overlap), and one that is a complete model for printers wide enough for it. These can be found on Thingiverse (two pieces for 300mm bed printers and one piece).
To assemble the three piece version, I used the bolts that attached the BC license plate to also hold together the plate holder itself. These bolts to affix the BC license plate were some 4mm bolts I had on hand and some washers that were big enough to not go through license plate mounting holes. I just re-used the car’s screws to affix the bracket to the car itself.
I printed the license plate holder in PLA filament. PLA is easier to print than other filaments, such as ABS, but it’s also not very durable. While I’ll likely reprint it in ABS at some point, I’ve painted my PLA prototype with some black spray paint for now so that is can handle the elements better, especially UV from the sun.
I hope you can use it and save some time, if its something that you need for your Italian car.
License plate hardware:
bolts: M4 x 10mm
nuts: 2.5mm (thick) x 6.75mm (wide)
washers