I wanted to make a couple of additions to your excellent article on wheels. A rule of thumb is if the wheel size includes a ".5",it's designed to be tubeless. Also,on the one ton duallies from the late 50's/early 60's,switching the 17.5's to 16's isn't hard on the front. (I changed on my '62 because I could get new 16" wheels and tires for less than JUST the 17.5 tires.) I used short shank mag style lug nuts and washers,had to drill the lug holes about 1/32" bigger for the sleeves to fit when I put 'em on my '62,but the 16's wouldn't fit over the big brake drums on the corporate rear end,so I was stuck with the 17.5's,17's,18's which are about the same price,or possibly going to 19.5's,which are more common than 17.5's but still about the same price,so no savings there. This is probably all academic by now-everyone's changing to 19.5's now. As you indicated in the article,it's a good idea to test fit new wheels before mounting tires on 'em.