Hello I have just moved into a house. The original owner was a cabinet maker of some renown, and every bit of work completed was brilliant, if slightly mental. One of these things is the front door. He made it himself. It's intricately carved and looks lovely, but the stile is only 67mm thick. Would it be acceptable to put a 64mm mortice lock into this door, or am I going to find it weakens the door significantly? I could fit a new door, but there is nowhere else this one could go and it is lovely.