I have tried some combinations of ProxyPass, ProxyPassReverse and ProxyHTMLURLMap but I'm still not having much luck. I just would like to be able to hit the printers in CUPS by going to www.printerhost.com/printers/printername rather than having to add a port 631 or have CUPS listen on port 80.

As requested, here is the configuration file:

LoadModule proxy_html_module modules/mod_proxy_html.so
LoadModule xml2enc_module modules/mod_xml2enc.so

NameVirtualHost *:80

<VirtualHost *:80>
   ServerName blah.yours.com
   JkMount /* balancer 
   JkMount /jkmanager jk-status 
   JkUnMount /cups* balancer
   ProxyRequests Off
   ProxyPass /cups/ http://localhost:631/
   ProxyHTMLURLMap http://localhost:631 /cups
   <Location /cups/>
     ProxyPassReverse /
     ProxyHTMLEnable On
     ProxyHTMLURLMap / /cups/
   </Location>
</VirtualHost>