If you simply keep up the maintenence and drive it now 'n then, you should be OK. I did examine one that was brought back from Hawaii after many years of neglect and it was virtually destroyed. Every horizontal surface had rust clear through- including both exhaust headers. A Chapter member did buy it for a song and spent a decade TIG-welding hundreds of little steel patches all over it, finally bringing the poor thing back to driving condition. He still has it- thats dedication!
Your other option is a 'car bag' made for exactly this problem, that pushes dehumidified low-air-pressure into a car-sized plastic bag to keep humid outside air away. Car collectors swear by them and they're not expensive.
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