Powershell ISE and multiple NAV-versions: Where to define which NAV-version ISE should use?

Hello All

I am working on a small Powershell script that will run a NAV codeunit. I recently installed NAV2016 (9.0) as a test before our upgrade sometime next year (we are now running NAV2013r2 (7.1)), so I have two versions running.

Powershell ISE automatically runs the 9.0 version (apparantly because that is the most recently installed?), but I want it to automatically run the 7.1 version.

So my question is: Where is the setting where you which NAV-version it uses as standard? Or alternatively: Can I define somewhere in a script that it should use one version instead of the other?

I have found a workaround, which is easy but not optimal: If I just take the "71" folder in "C:\Program Files (x86)\Microsoft Dynamics NAV" and rename it to"90", the PowerShell ISE program will run the exe-file in 90-folder, althorugh it contains the 71-version. But I whould much rather that the program just started NAV-version in the 71 folder.

Thank you so much in advance.

Regards,

Maria