Valve seat question…

Are they new heads and you’re trying to upgrade the seat material?
Or used heads with a problem?

I’ve had to swap the intake seats on some BBC PC heads before.
The ones that were in it were coming apart(pieces falling out of them).

My philosophy in those scenarios is to use seats that are “too tall”, and have an ID that’s “too small”, then I can machine it to match the original after it’s installed.