Hi,i recently bought a chrysler striper(15ft 1978)with a 50hp force on the back,i am very happy with the package but due to its age has a few cracks in the gel-coat(due to knocks and trailer roller pressure)and chips in the keel revealing the resin. What is the best/correct way to repair the hull,there are no leaks in the hull,the boat will be going into saltwater,is it just a case of filling the damaged areas will gel-coat?