He's becoming quite solid in the air, mostly for winning aerial duels after goal kicks or defending at set pieces while marking the most dangerous opp player when it comes to aerial prowess.
Unfortunately, he's not really proficient in that regard when it comes to attack. Just some flicks then and then, but he's not a consistent menace when it comes to headers towards the goal. If he was a bit better in that area, he would easily scored 4 or 45 extra goals each season.
I would keep Header at 78, maybe even slighly lower. But Jump is mid 80s material, even with that towering size.