Disassembly/assembly of Ruger KP90

[Buck]

I'm having trouble disassembling a Ruger KP90 (given to me as a gift). I got to step 4 in the owner's manual, and can't get past trying to align the slide stop retaining pin with the slide stop notch.  I'm new to semiautos, so that doesn't help.  I know there's some P90 owners here, so I'd really like the help.

[securitysix]

1.  Clear the weapon (make sure it's empty).
2.  Remove magazine.
3.  Flip ejector down
4.  Line up the slide stop with the disassembly notch in the slide and push the slide stop out (right to left).  This may take some doing if you've never had it apart before.
5.  Once you have the slide stop pulled out as far as it will go, you can pull the slide off.
6.  Carefully remove recoil spring and guide rod from the slide.
7.  Remove barrel.


You pretty much reassemble in reverse order.  The ejector can be pushed up manually, or by inserting a magazine.

[Buck]

That step 4 is what's kicking my butt.  I managed to put the slide into such a position as to be able to move it from right to left, but the slide wouldn't budge, so I'm thinking it wasn't the correct spot.  Could you elaborate on that part?