For running your car on unleaded, you should be fine if you fill it with leaded every few tanks. I'm sure there are unspeakable quantities of information available on the subject.

This reminds me of my dear friend frou_frou and her fondness for old cars. Although she did fall for the siren call of recent models with these newfangled 'technological improvements' and 'stuff that works' and so on. Her current vehicle is a 1970s BMW.

('Verity' is good, but I still prefer 'Lucy'.)