Using a parameter for TE Mode numbers

I want to sweep over TE modes in my geometry so I can add up the total power dissipated in my system.

When I make a parameter and enter it in the Port settings page (Rectangular Port, TE10), I get an error saying the mode number is invalid, regardless of what my parameter is set to. Setting it to 10 doesn't work.

Is my only option to specify a User-Defined TE Mode through an equation?

Thanks!