Excellent route. Climb through some thin face and pull out left under roof to main crack. Crack goes from fingers to OW. OW section is probably no harder than 5.9.
Location
This pitch is located on the left side of the Split Pillar. Belay at anchor before bolt ladder on P3 (5.10b traverse pitch) of the Grand Wall. Climb route and belay at the top (you can rappel from here) or continue up Grinning Weasel about 15 ft. and make an exposed traverse right to gain belay at the top of the Split Pillar.
Protection
Single set small, medium nuts; single set .5" (green alien) to 4" cams (C4 #5 camalot). Optional extra .33" cam (black alien), 1" cam (#.75 camalot), 4" cam (C4 #5 camalot).
Double up on the #4 camalots for sure, unless you like to run it out for a LONG ways. The OW is cheatable, so you don't really have to climb that style, but its more like 10- up there. This pitch used to be rated 11+, and is definitely soft for 12-, especially if you know how to jam!