I've had Commercial Instrument Helicopter rating for decades (courtesy of the U S Army), but to be legal for IFR in my 10, I had to get the Instrument Airplane add on.
When I called the Examiner, he initially said that he "doesn't do homebuilts". I was bummed out. He asked, "Is it a tail dragger"?. No, I said. I described a tricycle gear, 4 place, very nice machine. I also explained that is was an all Garmin glass cockpit, with the Garmin GTN 650 as the IFR navigator. He asked me to send a picture. I sent him a picture of the outside of the plane, and one with the panel all lit up. He immediately responded back, "OK I'll do it" :-).
Today when I was there for the ride, he actually brought a friend (an RV-8 owner) over to show him the plane, which made me proud, to show it off:-).
Anyway, the ride went well. I hand flew the 2 precision approaches (ILS and LPV), and the autopilot flew the VOR. I'm glad it's done. Now there's less pressure on staying legal VFR for my trips now:-). I really love this 10.