I pulled out my digital vernier caliper and measured the thickness of the handle including the wireclip height and got about 11.4mm as the width for the clip setup for right-hand carry. I then moved the clip over to left-hand carry and measured again, getting 11.5mm on one leg and 11.6mm on the other, telling me that the left-hand groove for the wire clip is 0.1mm to 0.2mm shallower than the right-hand side. I would not have thought that would make a difference but clearly it does. I've stopped carrying the Para 3 lightweight because I can't reliably keep the clip on through normal use.
It's a beautiful knife with great ergonomics, but since I can't keep the pocket clip on it, I can't carry it.