i just bought a '77 C-30 project boat. i'm selling my 27 after 4 years of fixing it up. the 27 had 'sister' stainless keel bolts installed alongside the original rusting steel ones. the 30 has its original steel bolts and i'm concerned that they should be replaced or 'sistered'. anyone have any experience with this? am i being paranoid? i can find 8" bolts online and would consider installing them if the concensus is that this is a good idea.