I'm a leftie and use conventional sticks, I've never felt it hampers me in anyway (no more hampered than usual that is!) and I really think it's a case of what you're used to through lots of practice. I don't see any problem in switching the sticks around, but I don't really think it's necessary IMHO...but whatever works for him I suppose
If he's already used to wheel then I'd say a left handed wheel set up would be the best option