Ok, not sure quite how to do this...

I have a system with a single interface and ip x.y.z.1
I want to run iptables on it so when it receives a http request it
forwards it to a.b.c.1 and the requests go through and everything is
happy.

I have tried using the nat table with:
-A PREROUTING -d x.y.x.1 -p tcp -m tcp --dport 80 -j DNAT --to-
destination a.b.c.1

That seems to ALMOST work. I can run tcpdump on both the x.y.z system
and a.b.c system and see traffic, but the system I am testing from
never completely connects.

Any experienced folks out there that can provide some insight?

Thanks in advance,

Brian