Another consideration about using any stainless fasteners, TRY to get rolled threads rather than cut threads. Rolled threads are much more expensive, and hard to find, but will eliminate most of your issues with dissimilar materials. Cut threads leave a very scaly finish which tends to rip material from the opposite material they are screwed into. Cut threads almost demand anti-sieze paste. Rolled threads have a smooth surface that won't gall as badly as cut threads. Stainless cut bolts threaded into stainless cut nuts are an almost guaranteed galling situation if not using anti-seize.
