8 to 10 hrs labor to change '225' head gasket ?????

This makes me wonder why the gasket blew in the first place......
I'm sure you could get another (good) slant 6 and have it installed for about the same money. A lot of people are practically giving them away these days.
Then i would get a fsm and tear the old one apart and rebuild it, then you know what you've got. It would be a great learning experience for you as well.
In my opinion, if you are going to have an older car, you better learn how to work on it yourself or you will pay huge amounts of money to keep it on the road paying mechanics for everything it needs now and then.
Most mechanics these days wouldn't even know how to do the job without a fsm in front of them, so you are paying them to learn to work on your car as well.