If you have already gone through the effort to pull the cluster, just replace the bulbs with LEDs 

On 28-Apr-2015, at 15:33, David Beierl wrote:

> At 02:29 PM 4/28/2015, Richard Smith wrote:
>> I have a VERY dim high beam indicator light - is this something anyone
>> else has encountered? Is it an old age thing, and a new bulb would help? A
>> wiring issue? (1985 Westfalia GL)
> 
> You will have to discover this for yourself, with a voltmeter if
> necessary.  But I suspect that if you pull the lamp you''ll find the
> capsule plated over with a fine mirror coating of tungsten from the filament.
> 
> Yours,
> David