Hi,I need to find a spare wheel for my 69' 3/4 T.I had thought the stock steel wheels would be 16.5's but when I looked at the tires they say to mount on 16' not for 16.5'.I also measured the diameter of the wheel from edge to edge it is 17'.How do I tell if they are 16's or 16.5's?Is there a way without taking the tires off?