[paleotrope]

This is a minor point but leaded fuel for autos wasn't phased out until much later than 1975.

[jmclnx]

My memory from back then is iffy as I was rather young. But I think you are correct, maybe it was a phase in.

I know I went looking for another vehicle back then due to lead and rumors saying unleaded gas could eat away at the engine gasket.

I ended up moving to a unleaded car in 1983, indicating I could still find leaded gas after 75.