They're not accurate enough for a good fit where the neck of the mirror sits in the gasket recess. Wasn't worried about the initial material quality due to them being a trial. The original was copied and then inverted on printing.
In fairness to the guy that did the copy/CAD files, he is not a professional and did it for a bottle of rum.
I've looked into having it done professionally, but I live in the back of beyond, so there are no firms local to do it. One firm I have contacted that I don't really want to post the part has said he wants £80 to create the file and then it was a batch run for printing.
When you see these car Resto shows doing stuff like this, it's very misleading to me. Maybe someone who lives in a city that has decent engineering firms local to them could have better luck than me.
So, bottom line, I've had some trial runs done in rough, but they are not accurate enough in their fit.