If this were my pool I would drain half the water to get the CYA down to about 60 ppm first. Then I would shock it (with either sodium hypochlorite or cal hypo) and keep the chlorine at 20 ppm until the pool clears and the FC is holding with no CC. Then I would make sure my FC never dropped below 5 ppm! And I would never, ever, ever use pucks again, just bleach!

If you are planning on keeping your CYA at 120 then you should get the chlorine up to 25 ppm and keep it there until the pool clears and the FC is holding at at least 8 ppm.