Installing a different version of the merge module depending on the processor architecture

Question

I have a Windows.net solution that deploys with a Visual Studio deployment project. My exe is a win32 application that works fine in either x86 or x64 windows.

However, I have included a third-party merge module (* .msm), which is available in x86 and x64 versions.

Now I could copy the entire deployment project and just change the msm, but I'm a lazy guy, and it would be best to include both msm in my installer and install only the module that is suitable for the processor of the client machine.

Is there a way to do this using Visual Deployment projects?
Merge modules do not seem to have the Condition property, such as included exe / dll files.