Alt Warning Lamp Failure Bypass? 86 W124 300E

[jeepingjack]

All,
As everyone knows when your Alt warning light fails to come on, in the key on position, your alternator will not charge. I have this fault 90% of the time the warning lights will not light and I'll have a no charge condition. But every once and awhile I'll have the warning lamps light as normal and the alternator will charge as it should. Now I have two questions:
1) What should I be looking for as a fault. I have checked the small wire from the alternator to the connection block by the battery (x35) contuinity is good. Next I'll check the wire from the connection block to the #9 connection on the instrument panel connector. Any common faults to look for?
2) Is there any way to hot wire this intermittent connection to get the alternator to charge. I tried connecting the warning lamp wire directly to battery voltage but did not get a postive result i.e. no alternator output. Shouldn't it be possible to bypass the instrument cluster temporarily somehow?