Brunorufusx5

I Bought a 16ft 1977 Apollo boat that was running last summer. the motor ran before i disassembled it. it has an i/o, omc 120. while i was towing it around getting it registered, the engine busted down through one of the engine mounts.
i moved the motor, and sure enough the stringers and motor mounts were rotted out. the transom could use a good redo also. i did a bunch of research online and noticed something about a product called "seacast". I was wondering if anyone knows about this product and situation and this type of boat and can possibly give me info and tips and possibly details about this model of boat?