The ‘J’ head is as good as it gets in the early 70’s.

They all suffer with valve seat recession and cracks etc.
Most would go with crack testing before sinking too much in them...
We also have some with excessive internal rust issues from ‘shelf sitting’ in damp environments.

Best of luck with Mopar finest small block!

Carpe diem, quam minimum credula postero, thanx Horace!

There’s no point trying to fix stuff that ain’t broke,,, 'but if ain’t broke',,, you is not trying hard enough...