R.J.:
Those pulleys look like Steeda u/d pulleys.
The toothed wheel and blue plate come off. Do not take off the snap-ring, it is part of the crank pulley balancer. You need a large flat washer and a NEW torque-to-yield crank pulley bolt from your Ford dealer. You can buy an ARP 12-point bolt that is re-usable (i.e.-- it is not a TTY bolt), too. There is a tightening sequence for the TTY bolt that must be followed. Search for it here or pick up a Haynes manual ($20) at AutoZone or Borders Books, etc. The Haynes manual has most of the torque specifications for the car and I think it is a very good investment.
The blue extension that is in the crank position sensor hole should be removed, too. You have to loosen the 3 bolts that hold the A/C compressor in place so you can lift the compressor out of the way to allow the removal of the extension bracket and the installation of the CKS. There should be an o-ring on the CKS, too, so oil does not ooze out of the CKS port. Tighten the compressor bolts evenly. Don't overtighten the CKS retaining bolt -- there's no need to snap it off!
HTH,
Chris