Storing Luggage at Universal

[nocturnal9]

I'm hoping someone can give me advice: I arrive to a Disney Park on a Friday morning via Magical Express. On Sunday morning, however, I'm getting a ride to Universal Orlando for the day before taking a Sunday night flight (likely cabbing it to MCO).
a) Does anybody have any idea if/where at Universal I can store luggage for the day?
b) Alternately, would Disney Magical Express my luggage Sunday morning even if I don't Magical Express myself?

Thanks guys!