Offset valve spring retainers or keepers ?

No all new valves. I already cut the valve guides but the cutter that I have isnt wide enough to cut the seat it does however cut area around the guide.

View attachment 1715597486
Yes, you're cutting for positive seals.
Theres another that cuts down that raised inner spring pad to locate a inner / double spring AND in the process you can cut the spring pad deeper.
Comp 4719
Howard 92070
For up to1.55 spring .630 inner
92062 is 1.44 you can find others.