67 buckets - what years will interchange

If those buckets have the headrests they are probably worth a lot. Had my 67 buckets
redone - at the time I could find the pieces that go in the seat for the headrests but
NOBODY had the headrests. 67 headrests are different looking than 68 and 69 and are
a different width -- can't put the 68/69s in the 67 buckets.