What parts are "rust colored"? Could be red mud, could be surface rust, or could be heavy rust scale...The steering knuckles, torsion bar keys, CV axle shafts, LCAs, and a few other parts I may be forgetting are all unfinished steel/cast parts from the factory, and will have a light coat of surface rust if they have not been painted. Scuff and paint if so. If the actual lift components are rusting, take it off, clean it up and paint it, or paint it in place if you can get to them.
As far as decranking it, just jack the truck up, allow the front suspension to droop out, and turn the adjustment bolts counter clockwise. Only do a turn or two, drop the truck down, move it back and forth to allow it to settle, if it is the height you want take it to get an alignment asap, if not continue until you get the height you want. There is no magic X turns=X inches formula, as the weight of the truck, fatigue of the torsion bars, etc. affects the height, so be patient and adjust till it is where you want it. Try to turn the left/right bars the same number of times exactly to keep it level side to side. If it becomes unlevel, then adjust the offending side until you get it right. Generally the bolt on the drivers side will be turned in farther than the passenger side.
