Its exactly the same dilemma that i had with 1 of my draftees. Mine was much tougher thought couz 6'3 high skill/potential C, with decent outside skills, but i already have some nice big men trainees, so i decided to give him inside training for 2 seasons. (that player is already part of my U21), then i advertise him, to a dwarf trainers, so with 2 seasons dwarf training, he will be a very complete SF, and the money that i got from him i bought my SG. Now if you can afford to change your training plan and from guards go to bigs then keep him. If not, the route that i gave you its a good option too.