PIC How do I get this off/out? Valve

[ScottsdaleSwim]

My friend has a leak coming from the waste line. I think the gasket is shot on the backwash valve but I can't figure out how to get the top off to replace all the O rings and the gasket.
I pulled the pin and two screws but something seemed to be holding it at the bottom and I couldn't pull it all the way out.

Sorry the pic isn't that great. My camera phone doesn't have a flash.

http://img153.imageshack.us/img153/8562/pushpullfh0.jpg

[ScottsdaleSwim]

okay-figured it out but thought I would post it in case anyone else had the same issue.

there was a cotter pin that was sticking out that had to be pulled and then the handle comes completely off. However, when we pulled on the piston, it still wouldn't pull all the way out. We used dishwashing liquid to lubricate the shaft and then pulled really hard.

replaced all the O rings, re-assembled and it works perfectly. No leaks!