Every book on arranging I've seen indicates that jazz terminology reads an interval in a chord name larger than a 8th to imply the 7th is present.

I'm not sure even Wikipedia agrees with you:
Quote:

A thirteenth chord is the stacking of six thirds


By my reckoning, that "stack of six thirds" contains a 7th. (Actually, the way the quote reads, it looks like someone edited two different ideas together).

For particular voicings you'll often drop notes. Since the 11th (not the ♯11th) clashes with the 3rd, so it's often dropped from the chord. And if you're voicing for four horns, you'll obviously have to drop out a couple of notes (typically, the root and the 11th), but still try to retain the flavor of the 13th chord. But even here, you'll almost always try to retain the 3rd and 7th - even if you drop the 13th.