LTM - Proxypass for a single URI with content response rewrite

I'm trying to publish an internal website (xpto.company.local/originalfile.php) but I want to present it to the customer as xpto.company.com/index.php. I can do the URL rewrite (request and response) but i can't figure out how to rewrite the content so that the customer can call xpto.company.com/index.php?option=1 and the LTM forwards it to xpto.company.local/originalfile.php?option=1. I'm also having no luck rewritting the response from the server (payload) on the LTM to change the internal url's to external ones. I've looked into proxypass but all the documentation and examples only talk about folders and not files.

Any help would be appreciated. The LTM is with v13.