The C&C 38 has a balsa bottom (beware) and build quality was highly erratic. Unless its already been done you will have to rip out the entire AC system and start again.
The CS are by far the best built of the Canadian boats but the Merlin has a significant flaw, the liner can separate from the hull around the mast step. The first sign of this shift is in the cut outs under the seat at the starboard settee. If you see fractures in the liner running from the corners of these cut outs go look at another boat. CS almost always t'd the propane locker drain into a scupper line which is unsafe. The Merlin will likely also have solid core copper AC conductors.
This is exactly the kind of information I was looking for. Thanks.