The JK does not come with any means to adjust your caster from the factory. If you have a lift kit with adjustable control arms, you can make adjustments to your caster with them. If you have a lift kit that came with cam bolts, you can also make a minor adjustment with them but, assuming you have them, I'm not sure what would be meant by them being installed backwards. They're just bolts with washers that require you to notch out your axle mount holes so that they become slots.