Since I mentor at a high school where the students are building an RV-12iS, sometimes I stumble upon something that might be useful for an RV-3B, which I'm building. I wouldn't steal any of the school's parts of course, but sometimes I'll borrow one to check for fit.
The RV-12iS lighting kit has a nifty wingtip fairing and I thought it might fit the stock RV-3B fiberglass fairings. My fairings are the white ones from 2012. Well, they don't fit at all nicely - but with considerable hacking they could be made to fit. Since they cost (March 2023) $75 per tip, it's not worth it.
W-1222-R or -L, EXTENSION, part of the LIGHT KIT -iS.
RV-3B, now working on the cowl.