I need some help. I need some identifing attributes to the 87-88 turbo exhaust manifolds vs. the 89-91s. I have a manifold here and I'm not sure which it is. Is there a difference in the angle to which the turbo mounts to it? Or a number stamped in it?
Pics of both would really be helpful.

 

The 89-91 manifold is divided. The 87-88 isn't; it also has that flapper thing in it. That's for that twin scroll junk.