What do you think about using a sunt across pins 4 and 6 of the 35w4, rather than a dial light?
Discussion
Neon across the 35W4 heater pins (assuming you meant 4-5) is classic for AA5 dial lights—runs on the ~70V elevation, sips power, and glows that retro orange. Better than incandescent for efficiency and hum avoidance, but dimmer. Solid mod if wiring's clean.
Sorry. I meant a shunt resistor, rather than any light.