Find this climb as the 'tower' of rock protruding from the West Face of Castle Rock, just above Polyester Leisure Suit. This is visible at the right hand edge of the West face route in the attached photograph.
Climb the Big Deal Pinnacle by doing the first pitch of another route, either Polyester Leisure Suit, or P1 of the West Face, or a crack system just left of Polyester, but right of the wide slot next to West Face. I suggest the latter of these options to cover more new territory it is perhaps 5.7 & protects well.
After arriving at one of the two trees, both with anchors, climb up the center face of the pinnacle to access some cracks, or go to the right-hand side, and climb a perfect hands and wide-hands corner for 30' to reach a rising left-hand traverse at a horizontal. (This can be intercepted from the face below as well, apparently). From the left edge of this, move up the edge of the tower and cross back right on another rising traverse on a horizontal--both protect well enough to be safe, but could be exciting. Finish via cracks on the right side of the pinnacle or on the west slab to the summit.
There is no good belay on the summit, but on the shoulder to the climber's right of it, there are cracks, blocks, horns, and a good belay seat.
To descend, finish to the summit on the West Face and do the standard descent, or scramble down to the trees below (climber's left, a 5.6 or 5.7 downclimb) or to the anchors above Bailey's Overhang or Curving Crack (easier?). Then rap off with a single rope.
A standard rack to 3.5" with extras in the hands to wide-hands sizes. Several long slings.
Today, I led the 5.7 first pitch just right of the wide crack, then belayed at the right-hand tree. Then I led leftish up the middle of a short, blank face; made an unprotected step left; moved up a short, shallow crack; then hand-traversed to the right along the upper horizontal (heavily lichened and exciting, 5.9+). Then I climbed straight up a hand/fist crack through a overhang/bulge (5.9+) and up the right side of the pinnacle's summit block. If you instead do the handcrack, flare, gully, etc., straight up from the right-hand tree to the bulge crack, you will miss most of the best action. Ryan Watts led the third pitch up to the scramble-off.
Just looked in Rossiter's 1999 guidebook. I think we climbed the route as he describes it. D'Antonio's vague description may not disagree with Rossiter's. I interpret Bubb's and Lefkoff's path as going up the obvious crack above the right-hand tree, which is to the right of the way we went -- at least (maybe) until the hand/fist crack through the overhang/bulge near the top.