On the pump install, yes, the lever goes to the left, push the rack to the left ( if you removed all 4 pumps either by sticking a finger in one of the other holes or by holding the shutoff lever full counterclockwise.
Put the pump in with the pin to the left and get it into the slot in the rack.
NOTE: there is very little clearance ( maybe 3/32" ) between the underside of the block and the top of the lever arm on the pump so the pump will appear stuck until the hold down is almost fully tightened.
If you put 1 pump in and leave the hold down a little loose the pump should rotate slightly when you work the fuel shutoff lever. This is 1 way to verify the pump pin is engaged in the rack.
If the rack binds or the pump doesn't wiggle, you may not have the pin aligned properly.
This, for me, were the two key things that helped me get it right. I did not even install the hold down bolt yet. Stuck the IP in, and wiggled the fuel shut off. I also made sure the IP and its hole were clean, and a slight coat of fine oil, (I used sewing machine oil) were on the IP barrel. That way the chances of it binding, ( when wiggling ) were reduced. I will say, almost everyone who is good at putting the darn things in, seems to have his own special way to do it. I could still kick myself for giving the tool away to a soldier, that helps install the IP. Its still a PITA, just a much less of a PITA.