Joker,
I can tell you...I have an opinion on everything, probably not right, but a opinion anyway.
The flasher has a bi-metal spring in it. Two different metals are sandwiched together to make a flat little paddle. As current passes through it,the paddle heats up. Because the different sides of the sandwich expand at different rates, when it gets hot, it curls over sort of like a banana.
When it "gets bent" so to speak, it pulls away from the power contact, and presto, your lights go out...paddle cools off, hits contact, light come on, paddle gets hot, pulls off contact, lights go out...over and over and over.
Yours won't work because you have the "Horizontal Model"...banana will only function laying down on the job, or a loose wire!
Stuart