After an easy drive (see the Spirit trailhead page for details and a map), we enjoyed the decorated pinons at Christmas Tree Pass and slowly realized that the turn to the DPS Guide's trailhead is now staked as closed wilderness. The new trailhead is on the main road (waypoint SPIRTH), which adds about a third of a mile and 150' of gain. Follow the old (closed) 4WD road from your car until it ends (waypoint SPIRTX, the old DPS trailhead) or until you think it's bending left away from the saddle at XTRSAD. Either way, get to that saddle and head downhill.
Staying high as you drop into the bowl containing the Yellow Stone Mine is bad, because you end up going in and out of steep ravines (adding up and down in addition to bad footing). Staying lower puts you on soft dirt footing, there's a use trail that's worth finding and following as you go to waypoint SPIR01. From that rib you'll climb steeply to the prominent notch in the NEXT rib (waypoint SPIR02). This notch is critical since it leads to the use trail under the cliffs between SPIR02 and SPIR03.
There's a big cairn on a huge boulder in the wash at waypoint SPIR03. If you cross there, you'll find the use trail on both sides of the wash. Climb steeply to waypoint SPIR04, then traverse up and left to the ridge at waypoint SPIR05. (I'm using waypoint names because this terrain doesn't have features that are easy to describe clearly. Follow the line on the map, or look for the plentiful ducks and hope you follow the right ones.)
When you hit the ridge near the summit, there is a nice flat area for camping, complete with fire ring. Follow the ridge north until you have to turn west, then scramble through a notch and cross a sandy area to the summit.
Spirit has lots of traffic, really good rock formations, a short hike, and an easy drive. We spent only 2 hours getting to the summit, 2400' round trip.
Next stop: Chemehuevi Valley