Last autumn, I put my car away for the winter, only to finally reveal a tiny leak in the fuel feed hose from the fuel feed pump to the hard fuel line at the back of the car. I had smelled gasoline when I put the car away since mid summer, but there was never a drop under the car, so I could not find the leak. By November, when I stowed the car--I finally found a tiny leak. It was at the crimp from metal to rubber on the feed hose. So tiny that it took some months to get to a minor "drip, drip, drip" condition. I let it drip into oil absorb; ordered a new hose from Dave Gallon, and put it off until this weekend.
I should note that I didn't feel the car was running 100% at highway speed. Maybe 98%; there was a slight misfire and hesitation, one that only the best of us might notice.
On Saturday past, I changed the fuel line, and "woke up" the car. I drove home yesterday, ~160 miles at about 70-80 MPH. No leaks, and the car's highway behavior is back to 100%. That darn pinhole leak introduced enough disruption to the fuel flow (or allowed air to get in or something) that the car didn't behave 100%.
Car is back; ran great. My hat's off and a nod to all the Aussies who drove long distances recently. You never know what you'll get with a very long drive in a very old car--and it takes a bit of spirit to do so. My small drive of 160 miles pales compared to what some did.