Changing the default MS Basic Sounds in MuseScore 4

Hi!

So I've recently downloaded the Beta version of MuseScore 4, and I have tested out everything, though I need some help with something.

Now I know that I can customize the different instrument sounds within the Muse Sounds library, which I find that the samples sound EXTREMELY GOOD and realistic, but I can't find a way to change the preset sounds within the MS Basic Default SoundFont. I'm not talking about changing the entire instrument staff, just the instrument preset sound from the built in SoundFont itself.

It was a lot easier to do within the versions of MuseScore 3, but with MuseScore 4, it's VERY confusing!

So I need some help here, please.

Thank you!