1970 LeMans Brake Light issue

[biggjuss]

My right rear brake light wont work. Bulbs all light with headlamps. 2nd element in bulbs just wont light up. I replaced all the bulbs and switched them with the left side...nothin different. Fuses all good. The light connections have some build up but nothing terrible. cleaned and replaced, still no go. Wiring to the connections look ok too. I can only see about 3 inches of each but the actual conection seems fine.
Any ideas??
Thanks!!

 

[melsg5]

Use a voltmeter and see if you have current. Any corrosion in the sockets or the ground wire will cause problems.