They will physically fit and function, however, you don't want to. The primary reason is combustion chamber size, which is substantially larger than early 289 heads, causing a loss in performance. Also, there will be little or no difference in flow, meaning no gain in performance there either.
All Ford heads had flame or induction-hardened seats since the 1950s. Unless damaged or ground-through during previous rebuilds, they will be fine with unleaded fuels. Standard 'hardened seats' from machine shops are no different than what is in there now, and it costs big bucks for exotic racing valve seats that street cars don't need. The primary causes of valve and seat erosion or recession is poor fuel and/or poor ignition tuning. Rich mixtures cause pitting or grooving, and retarded timing (especially at cruise) causes valve erosion and valve seat recession.
David