ktomi,
Don't get too alarmed about all this talk about new calipers and them not working because of surface rust, yes surface... it's heavy but it's on the surface. NOVAX5 was correct. Anyway three options... paint over it, wire brush/sandpaper or sandblasting. Sandblasting will give you that new bare metal look, many places sell a home sandblaster rig SEARS, Harbor frieght etc... Play sand from Home Depot works well in them. A wire brush on a power drill will work well on the flat aras that are easy to get to...but it won't get in the nooks and crannies. Lastly, and worst option, is to apply some rust converter/stopper, also sold at Home Depot, brush it on and it'll dry either a white or black chalky color that then can be painted whatever color you want... however the paint will probably start to peel fairly soon. IMO sandblasting is the best and easiest option. Unless money isn't a factor then as mentioned above buy new.