Getting up through the initial seam (past the initial overlap) is the crux on this climb ... be sure to place gear well at the bottom of this route. Gear is a little tricky down low and the pin just before the top is sketchy.
Start right at a drill hole, and wander up the face following the path of least resistance (generally to the left), moving back right to top out.
This route is located just past the initial few boulder problems you see on the left as you head down the carriage road. This is the left-most line up the white wall just past several short wide cracks.
Small gear for the lead; you'll need LONG slings to TR this route. Walk off left.
Worthwhile 5.7-5.8 face climbing on Top-Rope if that's what you're looking for, but not much special about it. Never seen anyone leading it -- some suggestions in guidebook that it's not so well protected.
Since I don't understand the Description given above (as of February 2012), I'll say here how I've done it a couple of times (only on Top-Rope).
There are two "blast holes" visible at the bottom of the Brat face, vertical rounded hollows remaining from drilling into the rock to place explosives, to blast away some of the rock to make a wider flat space to build the road. The right-hand hole is roughly underneath the obvious crack for Brat Direct. The left-hand blast hole is the "official" start point for Katzenjammer -- roughly 7-9 feet left from the obvious Brat crack.
Climb the face above, with various easier or harder lines. I've read about an option of diagonaling Left, never tried it. But for Top-Rope, surely it's easier to set up TR for climbing more like just straight up - (perhaps requires a 5.8 move or two?) - with the finish say like 8 ft Left of the top of Brat, roughly on the same wide ledge.
Start variation: It's much easier if instead start farther Right toward Brat, then diagonal Left up the obvious less-steep ramp, then traverse a couple of steps further Left with feet on ledge, to rejoin Katzenjammer - (also used as a non-Direct start for Brat).
And even if using the "official" start at the left blast-hole, it's definitely easier if use the edge of that obvious ramp for hand-holds. If you're much less tall than say 5 ft 9 inch or 5ft 8inch, then it's a tricky challenge if eliminate using the edge of the ramp for handholds.