Nick, if you climb on the Triumverate Wall, you can rappel The Rib (https://www.mountainproject.com/v/the-rib/106411652) with a single rope. It's been a while since I rappelled this, but my friend's comment, which I believe he is talking about the second rappel anchor here:
"if you rap climbers left off the ledge with the bolts, you'll make it with a 60 to the raised platform above the trail... at least my 60 makes in no problem. If you rap up the way you climbed, you'll probably run out of rope and risk a bad swing. It's definitely not a good rap line, but I do like being able to get down w/o carrying a second rope."
It's not a good rappel line, if you are inexperienced you may want to track down somebody with a second rope to avoid the shenanigans associated with getting down safely with one rope. That being said, if you are in need of somebody showing you around, send me a message as I might be available to show you around.