Gwen,
I think the problem is that you are in Cabo for such a short time (7 a.m. to 2 p.m.) so I think you will either have to get up with the chickens to go on the tour.
You can do the City Tour, which stops over at San Jose del Cabo, or you may wish to just do the glass bottom boat ride out to Los Arcos (45 min tour) for $12 a person.
I find that usually by the time we dress, get something to eat, etc, that we don't get into Cabo till about 10 a..m. so we usually poke about town, check the email and stop for a drink and some lunch by the marina.
Harry