We rebuilt a 90+ a couple of years ago. Our front brake had its original paint, so we asked our painter to match the rest of the bike to this. we agreed on the colour match he found, however once we reassembled the bike, we found that the colour had changed slightly, so had to repaint the front brake (which had been the only part in its original, but perhaps faded, paint) to match. I've seen quite a few 90+ bikes at shows, they're all different shades of gold!!
Best of luck,
Roger