This line is described in Hill's (1983:109,111) "Hikers and Climbers Guide to the Sandias" (I'm working with the 2nd edition; I haven't seen if this description has changed in the 3rd edition). Schein's (2003:75) "Sandia Rock" describes a line that may have a slightly different first pitch. I followed Schein's line, so I can't comment on Hill's full route.
Pitch 1: From the top of the pillar at the far left side, face climb through discontinuous cracks and seams, finding pro where you can. Stay within about 20 feet of the left side of the wall, aiming for the left side of a roof. Note: Hill's photo topo (1983:111) goes right of this roof, and his text doesn't mention it specifically; his narrative description takes you up a crack and through several bulges, which may lie farther to the right of the roof. Once through the roof, more face climbing takes you to the left end of the prominent ledge that crosses the face (the end of Pitch 1 of the West Face Traverse); belay from the two bolts and fixed pin at this point.
Pitch 2. Hill and Schein appear to agree. More face climbing through discontinuous seams, staying within 20 feet of the left side of the wall, takes you to the top. I found a 5.8+/5.9- crux in this section that briefly pushed me over to the far left arete, but YRMV depending on route selection. You could probably escape rightwardly into the top pitch of West Face Traverse if needed.
This route climbs the far left side of the west face of the Tombstone. It's easy enough to approach if you start from the southwest corner of the formation (at the flat-topped luncheon pillar). Traverse north underneath the whole face, and then ascend through blocky 4th class terrain to the flat top of a pillar at the very northwestern corner of the formation. This is the start of the route as indicated by Schein. Hill's photo topo (1983:111) also suggests this pillar is the start. However, Hill's narrative description, which has you starting "about 25 feet from the north end of the west face, atop a small flake separated from the face," would appear to put the start much farther to the right (see the beta photo), at about the location of the little pine tree illustrated in Schein's topo.
At the top, walk off to the east and then south.
Standard rack of cams & nuts should do, but doubles of finger sized cams would be nice, with plenty of runners too. Some of the loose flakes and blocks on this route may warrant its consideration for a PG rating.
There are two good bolts and a fixed pin at the belay atop Pitch 1. There are plenty of trees and blocks to sling at the top of the formation.