Thanks Jim. Can this be inside a VirtualHost container? Right now it is outside, just at the end of httpd.conf, and still NOT working.
I even changed the 0.0.0.1 to 127.0.0.1:
ProxyPass /site/images http://127.0.0.1:81/
ProxyPassReverse /site/images http://127.0.0.1:81/
This is still giving 404. In error_log, apache just says file not found or unable to stat.
I have checked through "httpd -M" and all the proxy modules are in fact enabled!
What am I missing? Thanks.