Came here to say this, love the blueish-turquoise of the '68 Custom series. They come stock with a #47 bulb but you can replace it easily with a #44 for a bit brighter light.
If we're not talking strictly Fender-branded amps but this jewel type, if the amp uses the #44/#47 mini bayonet bulb, a clear jewel over it looks natural, clean, elegant, etc... I've done this with my DC30 and AC15HW1X, it's much more like an extension of the panel and a natural part of the amp rather than just a red or green light out of place.
(only picture I have of the AC15)