1931 Auburn Tire Sizes

According to Floyd Clymer's book Data Book of Tires published in the I believe early 60's the 1931 and 1932 Auburns used a 6.00 x 17 tire. I have 6.00/6.50 x 17 tires on my 1932.

I have seen all of those used and seen references to 5.50x17 in print.
That said I am using a combo size 6.00-6.50x17 on my 1932. Others prefer the large tire look and use up to a 7.50x17.

You have a few choices among the various hobby tire dealers.

Can someone tell me what is the correct tire size for a 1931 Auburn 898 sedan?

6x17?

6.5 x 17?

7 x 17?

Any guidance would be much appreciated.