I had the same concerns when replacing bolts on my LR Defender. You have to consider the risk of corrosive reaction from the stainless steel bolt contacting with the metal/aluminium bodywork, whether the bot requires high tensile qualities, what grading of SS bolt etc etc. A simple sounding idea turns into a head scratcher! I dipped my stainless bolts in ACF50 paste, but that will wear off with weather over time.