This route is a short talus/scree slog accessed easily from the main Lassen trailhead that can be completed in a couple of hours or less. One can see the route shortly after leaving the main trail headed west into the small cirque on the south west side of Lassen Peak as it goes straight up the east side of Eagle Peak.
Although it is rated at class 2 the rock is all loose and very unstable. It is difficult to make one's way up, or down for that matter, without losing one's footing and sending rocks sliding downward. This makes for not only unpleasant climbing but, potentially, unsafe climbing as well. For these reasons I do not recommend using this route. However, with a good and stable snowpack this route would probably improve significantly.
Follow the directions to the main Lassen Summit trail head and instead of following the Lassen trail, stay just left of it for 50 yards and angle left following the light use trail west through the cirque. Eagle Peak is immediately in view in front of you. The route begins at the base of the gully and can reached by picking one's way up the boulders and slabs.
Once at the bottom of the gully you can pick your way up the route. I believe that I found the climbing more stable and easier staying climber's right. After reaching the top of the gully it's an easy stroll to the summit proper.
No special equipment is required for this route unless there is snow in the gully. Bring crampons and an ice ax in such conditions.