Well, I'm not an elec wizard but here's what I've determined. (2)x 100 watts= 200watts/ 12 volts=16.6 amps. Our stock foglight circuit is 15 amps, so two 100 watt foglights is a no go. I ordered two 55 watt PIAA 540 series. (2)x55= 110 watts/ 12 volts=9.1 amps, within the stock circuits limits, so all shouild be well. For comparison, the stock foglights are 42 watts (2)x42=84watts/12=7 amps.
If I'm not mistaken, there's already a relay in the engine compartment fusebox. I think it should be good as is, other than removing the connectors that hook to the stock lights and installing the PIAAs. I should have stated that I installed a winch bumper and could not reuse the stock fogs. I was unsure what wattage our stock harness could handle. I hope this info is useful to others who would like to have a simple soloution to using aftermarket fogs.