response page based on mod security rule in error logs?

Hi, I would like to accomplish the following.

Modsecurity is enabled in NginX and I want when some false postitive hit is opened, some rule blocked some page the response page to be shown with the error code from the modsec rule. For example you have been blocked by mod security rule "XXX" as the rule is get from the logs. I think this eventually can be accomplished using if and map variable in the nginx configuration + some dynamical error page, but I am completely not sure. Can anyone share it's expert advice or experience?

thank you in advance!