I wouldn't necessarily assume that any color on the tail light is what you expect...even the black. The wires on my '95 are black=ground, blue=tail, yellow=stop. The wires on my aftermarket tail light are green=ground, yellow=tail, brown=stop,.
Wired so everything is working correctly is black to green, blue to yellow, and yellow to brown.
Wired so everything is working correctly is black to green, blue to yellow, and yellow to brown.