Nope it's not
One my Fastback I had those Yellow lights as the standard setup.... 6v. But when I did the 12v conversion I had to 'loose' them. Until one day I mentioned to my previous boss(Beetle garage) that I would still like to have them, but I cant with the 12v. To my surprise he said that those yellow bulbs does indeed exists in 12v.
So you are in luck, all you have to do is find the same haed light bulbs you have, but in yellow! :agree: That yellow 'tint' that you see is actually the reflection from the bulb itself.