TFI Distributor O-ring/Gasket??

Is there supposed to be an o-ring or gasket between the TFI distributor and the distributor cap?  Replaced the cap with an MSD one because the cap that was on there was showing signs of poor contact between the rotor and the terminals.  Now that I think about it, there was no seal of any kind when I pulled the old cap and I'm wondering if there should be?  I can't seem to find one or a part number, but thought it was worth asking.

Thanks,
Nathan

No gasket.

Yup.  And, there isn't supposed to be contact between the rotor and the terminals.  If they touch you'll have problems.  But, they are supposed to be really close when the spark jumps.