To install, copy the "pms50-instrument-gtn750" folder into your MSFS Community folder, then start MSFS. 

Once ingame, follow the "Documentation/documentation.pdf" -> "Premium extension activation" by going to the GTN750 license menu. You can enter any random numbers for your license code to activate it, for example:

00000000000000000000000000000000
68924512369843826905428543209854
21385973428957438295843295893289
89929534895820081975034715713427

If you encounter any problems, deactivate the license and enter a different one. Also try restarting MSFS between deactivating & activating.

Be aware that future updates of the GTN750 need to be cracked again, meaning you cannot download updates directly from the pms50.com website without losing premium functionality.

About MSFS 2024 compatibility, read the following page first: https://pms50.com/msfs/msfs2024-compatibility/