[RICK LAKE]

Tom Howland Tom It sounds like alot of work to repair this head. Good thing is it's aluminum. Tig in alot of metal to build up the seat area and cut a new seat and install a valve seat. I would check the cost of a blank head and have the parts swapped over with just valve seats being machined to match the valve angles.
Joe B. is in Fresno and has more the 60 years of special work.

You might also save some money and find a guy who can tig and fill in the area. This is a special skill. when done right, last a life time, when not Junk city.

IMO replace the head and swap over the parts. Down the road you might find someone who would be happy to repair it or even Dart. This way you have a spare head if needed and don't loss time for driving season. Just a thought. Rick L.