The easiest way up Antsell is to leave the PCT and go up the short/steep Class 2 gully. The gully leads to a fairly easy Class 3 section you'll need to climb. Once on top of the Class 3 Section, you traverse a short distance over the branches of a tree to a short gully and go up it. At the top of the gully, it's just a hop and skip to the highpoint.
Here's what the Class 3 section looks like:
Look for that little tree that's in the picture and you'll know where to go up. The class 3 section is on your right side (if you're facing the top of Antsell) when you reach the end of the Class 2 terrain in the gully.
Right now there are a lot of ducks in the gully, and a use trail most of the way up. It's amazing how those use trails have developed over the last few years. There didn't used to be a use trail or ducks all over the place in the gully.