Upsizing an eel (Medium) and dire eel (Large) to Huge yields the following ability scores:
Eel: Str 29, Dex 11, Con 20, Int 1, Wis 12, Cha 2
Dire Eel: Str 27, Dex 11, Con 18, Int 1, Wis 12, Cha 2
So Str 27-29, Dex 11, Con 18-20, Int 1, Wis 12, Cha 2.