Hi. Brand new to the forum. I recently purchased a 1978 450 SL. I have no brake lights. Other lights are working. Fuse 10 was blown, but I replaced that. Switch seems to be working. I'm not sure what the resistance should be at the switch though. It seems I have power at the switch (6 volts). No power at the brake lights themselves. Anybody know which particular gremlin I should chase now?