Ok, I got the new cylinder in, but it seems the the shaft is not positioned correctly (removing the gasket helped a ton). The flat part of the tab on the old cylinder is positioned horizontally, while the new one is vertical. I can't figure out any way to adjust the new one. This means that I can lock the door (but not unlock it) and vice versa. I think I got a defective lock from Jim Carter. Has anyone gotten better locks somewhere else? Thanks for any input, it's very helpful at this point.
-cale