I have a 1972 Honda CB350F and I got the new tail light from DimeCity. I think it was called the Buffalo style Medium tail light. The tail light turns on and works fine when I switch on the headlight, but whenever I activate the brakes (brake light), the fuse gets fried within a second.
I hooked it up the exact same way as my stock tail light (which works perfectly fine with no trouble). Here are some pictures of the connections with labels on the wires. (Sorry for the jumbled mess)
Stock Tail light connection:
-G = Ground (Solid Green Wire)
-P = Power (Solid Brown Wire)
-L = Switch (Green Wire with Yellow Stripe)
New Tail light connection:
-Black wire -> Ground
-Red wire -> Power
-Yellow wire -> Switch