I get over 200 miles on a tank of gas and that is usually a long enough distance that a break in driving is a relief. For where I travel, I see no need for a larger tank or an extra tank.
However, a friend went on a cross-country trip last summer in a 1953 GMC 1/2 ton with Hydra-Matic transmission. If he had only the 17.5 gal tank, there were stretches in the west where he would have had to use containers of gas (he installed a second thank under the bed).
