If you're into reading through 36 pages of morphology and aspects of sacred architecture plus my bibliography, you are, of course, more than welcome to try it:
The Slow Burn and the Flash in the Pan: Teotihuacan and Xochicalco: Broad Similarity and Focused Differences
If you're just interested in representations of the plumed serpent "deity" of Mesoamerica, then start on p. 26. There's about 4 pages of info comparing the serpents at both sites. I am unconvinced that they're the same one.
This paper got so out of control so quickly it wasn't funny. I'm terrified of being seriously docked for overkill.
Target range for these papers was 10-20 pages, though that was never explicitly stated.
I'm also unhappy with the conclusions, all told. They're slightly unclear and could have been better presented.
But I am, on the balance, very happy with this paper.
Now, off to finish that GSP before midnight.
I'm applying for clergy status today.