K0 though K5 should all be the same basket, steels etc. In 1976 they changed the basket on both the F and the K (not sure if the 75 F has the same as a K basket), and then again in 1978 for the F only (they also increased the spring pressure and changed a few othe pieces). As far as I know you can use the 76 basket on the earlier bikes and the plates and steels are all the same, the F in 1978 has different sized shafts and the baskets may not interchange.
what are you trying to do?