Stainless steel fixings

Quoted text begins.Good point about Galvanic reaction causing crevice corrosion. Choose metals
close to each other in the Galvanic series. The Statue of Liberty's inherent
problems you are probably familiar with:
http://www.corrosion-doctors.org/Aircraft/statue-saddle.htm
End of quote.

or...use a barrier between the dissimilar metals, like silicone or
rubber. of course, you also have to consider the effect the barrier
would have on all the various materials.

Jerry V