Why no brake light on left?

["Beth & Ken" <bethken@erols.com>]

I know...buy Dan Master's book. My GT6s taillights work fine, but only the
right brake light comes on. The bulb is fine. I know this is probably an
elementary question, but what's the most likely reason for this (I am an
electrical moron awaiting Dan's GT6 / Spitfire book with baited breath)

ken shapiro
baltimore
1970 GT6+ KC81872L