It's actually easier, in theory.
In CPS when you switch to Expert View, the Frequency Ranges section becomes visible on the Radio Information screen. There is an option to Allow Invalid Frequencies that can be enabled, which will then unlock the UHF2 Used in Codeplug option, allowing it to be enabled. You can then enter 470-512 frequencies without it displaying any invalid fields.
The trouble is that the radio itself does not take kindly to being programmed out of band. I was unable to get a 7000 UHF1 model to stretch up to just 800 kHz into the T-Band range, much less a full 6 MHz. That was for RX, by the way.