Gold is 1300 today.
In 1968 Gold was 39, but that might have been under government control at the time, so I’m not sure if it will be a free market comparison.
In any case, it’s 33 times more today. That says the Chevy should be about 125,000 today, so something is obviously wrong with the value of gold in 1968.
You are correct. Gold was being constrained by the US government. It was allowed to float later in the 70’s.
A better comparison would be late 70’s or 1980 when gold was freely floating.