Yes on the OshKosh and Autocar FWDs the rear singles are narrower than super singles. You're right you don't want to run a big floater, But also the are not as narrow as typical Duals are either.... Usually too much load for one narrow tire!!
Hi IC- Smoke. I was just through your neck of the woods yesterday. I noticed that the OTP has Peterbilts. Some nice looking trucks, I was wishing I had my camera so I could have posted some pics on here.