my replacemnt hatch has the third brake light atop the hatch glass instead of the spoiler .when i looked at the pics on here i noticed 89 doesn't have this.

It's an earlier year hatch, from 82-86 I believe (I know someone else more knowledgable knows)

I think in 86 or 87 they moved it to the spoiler.

If the third brake light is mounted on the top outside of the glass it is an 86 hatch. 86, as far as i know was the only year for that third brake light.

86 is the first year for the third brake light and they are all on the outside top od the glass. 87 was the transition year. Any Camaro with a rear spoiler the brake light is mounted there, so all Z28s and IROCs got the spoiler mounted one. The Sport Coupes without the rear spoiler had the glass mount third brake light.

Actually, there were 3 designs, the ugly outside top hatch glass mounted 86, the spoiler mounted 87-89, and the inside top hatch glass mounted 90-92.

Its either an 86 or very early 87.

my 91 has the light in the back hatch on the glass. i know that 90-92 had that but it is hard to say since any thirdgen hatch will fit any thirdgen.