I would higly recommend watching this guide. It is an old guide but I think there weren't significant changes if any.
The command panther skin is made like every other skin the only difference is that the skin is then forced on the command panther entity file in the attribute editor.
Can you reference mod skins in tuning packs like custom icons?
I've read conflicting information so not sure on it. You mentioned here
https://www.coh2.org/topic/94047/custom-vehicle-skin-in-tuning-pack that it can be done, but how would you include this in your own tuning pack?
I have custom icons in data\ui, but would I need to include the skins in data\art ?
edit: seems like this tutorial implies that you can as well
https://www.youtube.com/watch?v=y43EGd2vHSE
but when he creates a skin pack how would that be used in the tuning pack? Im assuming there is some syntax for ModSkins_skinID_summer _winter etc.