Quite a few variants have already been developed around the fighter’s lifespan. These have provided the T-45A, that is a two-seat variant also utilized by the US Marines, along with the T-45C, an upgraded version with a glass cockpit and other augments, which currently serves as a design for T-45s https://www.metooo.co.uk/u/66ea9491129f1459ee6c7b6b