I would strip him, not clip him. I hate seeing a wire get clipped, it ruins the coat, (makes them fluffier). I hand strip Oliver, even though he's a mutt and won't ever be shown. I also stripped my sister's westie. The fluffier coat holds the dirt better. Oliver can be head to toe mud, but a quick brush after he's dried, and he's perfectly clean again.
Hand stripping can be a bit time consuming, but it's easy to do yourself. It takes me about 4 hours total to do Oliver, my 35lb dog. and I do it 2-3 times per year.