I'm working with MTM and have a question regarding shared scripts.

Here's the scenario.

General test scripts that are applied to three different branded websites. The test steps are the same, but the URL for the websites are different. I've created a basic MTM script using some shared steps that do the following:

1. Open browser (shared script step)
2. Navigate to the URL

Initially I had the URL navigation in a shared script to go to Site A. What I'd like to do automate (via action recording) go to Site A, and then be able to reuse the same script to go to Site B and Site C. What I'm finding is that unless I create a complete new test for Site B and Site C everything goes to Site A.

Is there a way to paramterize the shared script so it can go to the all three sites and I only have to maintain one test? Right now I'm maintaining three different tests but that seems to be too much maintenance, especially for such a simple test.