fender style pilot light fixtyres

[scole]

can they be connected to 120 volts with the correct bulb?

[tekhed7]

Ugh! Well... yes & no. You can still find what I believe are MB120 miniature lamps out there that will fit in a socket meant for a #47 bulb. Unfortuntely, the socket as used in a vintage Fender amp, is not rated for use at 120 volts & might short or arc out. There's only a small fiber wafer disc between the socket's support flange & S-M-O-K-E.
Stick with 6 volts & play it safe.

[Steve Conner]

You can get 120V and even 240V neon lamps that fit them, too. But yes, ugh.