Gas Prices in Canada for US travellers

Before I made my trip to Alaska, I did my homework, starting with the US Customs office in Cincinnati, where I live. I opted for the full passport rather than the US/Canada pass because I thought I might use it for other foreign travel, but I never did. I also got an American Express credit card, because its widely accepted around the world and the bill is automatically converted to US dollars. That took care of gasoline. They also let me convert some US dollars to Canadian dollars while I was there, pointing out that 100 miles north of the border, I shouldn't expect stores to know the current conversions. I still have a little bit left. The speedometer in my 'C' shows MPH as well as KPH so I was good to go - until I crossed the border in Sweetgrass, MT. and came to a bridge with a superstructure with the clearance clearly posted in meters. Pulled out my trusty laptop and found that I was good to go. The last thing that bit me was a grocery store meat counter. Everything was priced in grams. So I just ordered 8 slices, and I still don't know what that conversion is. That took care of everything but Starbucks coffee. And Tim Horton's took care of that for me. I see where Tim Horton's has started to invade in Ohio (several in Dayton) and probably other states.
One more thing. Don't lie. If the border patrol agent asks a question, he probably already knows the answer. He asked me if I'd ever been fingerprinted. I said, maybe when I joined the Navy, but I don't remember. Good grief. My fingerprints were on my passport that he was holding. He let me pass.
It took me awhile to figure out why I was just waved thru into Alaska, and back into Canada and the US heading home. Duh. Ohio has front license plates.