When I did my restoration, I changed out all the bolts, washers, nuts, screws, etc with stainless steel ones. I know in some cases the bolts might have some difference in strength, but where I used them I don't think it would be a problem. I just did not want any more rusted bolts to show up in time. Peter is correct, there are a few odd sized MM bolts that I could not find an SS bolt to replace it, so I purchased from MBCC the new replacements.
Bob