Nankoweap is great fun! I've enjoyed two trips there, and boy, the trail is a lot easier now than it used to be.
Here's a suggestion that might be worth a shot for your ride: Call up one of the motels on the AZ Strip (there are only 3 — Cliffdwellers, Vermillion Cliffs, and Marble Canyon Lodge) and ask them if they could suggest someone you could hire. The workers there are pretty isolated, they're not making a ton of money, and they might be up for making a few quick bucks. (I guess if the Strip motels come up empty, you could try the same thing with the motel at Jacob Lake…)