Loosen the bottom bolts in the Control Rods about 3/4". You may even have to take then all the way out to position the shock and mount hole so they line up w/o force. You also have to loosen the track fully.
If you do take the Control Rods' bolts out to install the shock, then you can install one Control Rod bolt w/o the plastic spacer to "catch" the Control Rod. Once you "catch" the Rod, tighten that bolt to pull the rod down. Then install the bolt on the other side with the spacer, Then go back and install the spacer on the first side.
In the above, I am not talking about the bolts that hold the rods' lower mounts to the rails. I am talking about the bottom bolts that hold the Control Rods together (i.e. They hold the lower Control Rod mount to the Control Rod. )
You can also do this same trick, when installing the skid. For installing the skid, that 3/4" takes all the fight out of the job. No need to take the bolts all the way out.