Installation keep current config


I am currently running the 2015-02-15 version of the NSClient++ and looking at upgrading to the latest with the op5 Monitor settings. The previous installation was just default installation. This client has been in operation for about 3 years and some systems have modified nsclient.ini files. Is there a way to install the latest client with the op5 Monitor settings while maintaining the current nsclient.ini file? And do so with a silent installation so I can use our deployment tool, BigFix to deploy the agent.