Hi Bill:

Whenever possible, I replace those grain of wheat bulbs with leds. You will
need a current limiting resistor. The led has a limited pattern of light,
so it will not work if you need light from the side of the bulb. Most of
the time, the led will work fine - and be permanent.

You can choose white or various colored ones. In some radios, the reduction
in battery current is substantial.

Colin K7FM