Install test and production outlook addin at same time

I have a pretty complex outlook addin that we have developed for our company.

The same users that use it in production are also the testers.

This leads to a lot of confusion and frustration as they have to uninstall the production version to test and then reinstall the production version when done testing. This is error prone as sometimes they forget to uninstall the test version. Also, The automatic updater will pick up the test version and install it on the non-testing user's outlook.

I would like the following:

1. Allow both test and production builds of the addin to be installed on the same person's outlook at the same time.

2. Use a different icon for the test version; perhaps just overlay "test" on the icon.

The addin communicates to web service so the test version will have to know to switch to the test URL.

What is a graceful way to achieve this?