Dana,
With the 392 stroker you're very near the "big block" as far as cubic inches go. The GT40 and AFR 185 heads are slanted toward the 302/351 size engines. You'll be happier with the AFR 205 heads. For mine, I went with the Victor jr. heads and intake and don't feel bad about it at all!
If you're still not happy, then your next choice would be a good stout roller cam.
h dog