This picture shows the old base we are referring to.
This picture shows the old seals vs the new hand tight ones.
This picture shows you how to take the silver seal off the new hand tight seal kit, and use the old red washer off the old Wagner seal kit. This is of course assuming you still have the read washer. For as wear, the part that normally wears out is the white concave part of the seal that touches the tip. (This part can be scored by reversing the tip with a large particle stuck in tip or such)