Hardened valve seats - do they really matter?

Yea, as I read through the comments more, I think I'm just going to use the head as is and later when I find a 73 and up head with the factory hardened valve seats, I'll mill that one and swap them out.

I plan to daily drive the car as I have daily driven several old mopars already and I like to tow my little mower trailer around and let the car be a car and do car stuff.

You used to be a traveling mech. , did you not ?
I noticed you may have a lawn business now ?? Pretty industrious girl ...