I think in this worst case scenario, even that one last Bitcoin could be hard-forked to make more than 8 places after decimal right?
Correct. There is a maximum of ~2.1 quadrillion unique transaction units right now. This could be increased if necessary, but I doubt that it will ever be needed.
If I remember correct what I read about the early days of Bitcoin there were not even 8 decimal places?
I'm not sure about that.