We extend to you a cordial "WELCOME ABOARD !" Come on in, make yourself at home, we are a friendly group of enthusiasts, and we also appreciate the classic Chris Craft Roamer, Corsair, and Lancer boats too , as they are all on the same family tree and share much in common !
My background is mostly in cars but seems to translate well to my newish love of vintage boats. As a general rule making upgrades, changes, or wholesale swaps(as in engine, transmission, etc) will not hurt value, historical significance, or collectablility...AS LONG AS YOU STILL HAVE ALL THE ORIGINAL COMPONENTS!. I can remember in the late 80's the guy who taught me the collector car business taught me there's nothing wrong with drag racing your COPO 427 Camaro as long as the motor and trans are on stands in your garage and you blow up something else. As long as you can go back to original without modifying what was originally factory equipment, go for it.
If you have a chance to buy some piece of mind and a layer of extra protection by converting to closed cooling, do it. If you ever sell the boat or show it, I'm certain those who matter will appreciate the fact you cared enough to protect the boat and save the original parts. Just my opinion. Some day when we are all at the "Lancer Nationals" I'll share with you all who my mentor was.