Got to level 100! Managed to get the Jumbotron to lvl -1, but it still acted like a normal lvl 1 Jumbotron. After you get around ~6 of any upgrade, it becomes unable to appear on the lvl up menu until you exhaust all the possible options. At that point, any upgrade (except for Walk Off Homer) can show up randomly in the 3rd slot (including double cleats). I only got around ~3 Cleats upgrades because I find it hard to control the character when he moves too fast.