That's 6c+ once it's wired. I think quite a few of those routes are so short and intense and powerful that they're hard to grade though. This also makes the few similar routes at The Wave (the lower Quarry) brilliant fun and well worth a visit if you live in the local area especially as they're open all year round. Coming from further afield can be a bit risky with the seepage, like there probably is at the moment, if you just want to climb in the quarry.
The guide is the trad Avon and Cheddar guide which details the old access restrictions and until the second topo comes out (they're having trouble sponsoring it) (you can update your guide information for the ret of the gorge with the 8 updates from the Cheddar Gorge climbing project which you might care to contribute to), and some sport grades are available for the Quarry in the UKC logbook.
There's a mini boulderfield below the Quarry too.
