I recently (this past weekend) went through this same ordeal. I could NOT get the new slave cylinder to fit between the clutch lever and the mounting area. I used a breaker bar to push back on the clutch lever, felt something "slip", and the clutch lever got quite loose - and then fell out! I checked everything and nothing was broken, so I put the lever back in, and lo and behold the slave cylinder slid right in, fairly easily. I think I had pushed the clutch lever to far onto the ball stud on the transmission and changed the geometry such that there wasn't enough clearance for the slave cylinder.

As far as bleeding it, I had pretty good luck with rotating the slave cylinder so the bleed screw was facing up. Makes sense because the air will accumulate at the top of the slave underneath the bleed screw. I still need to get in there and bleed it some more though... it loses pressure when it sits. I probably foamed the oil up bleeding it and I need to wait for the air to come out of solution and then rebleed it.