The smog pump in my 72 has developed a deep tapping noise. Any ideas before I tear into it.

Correct me if I'm wrong, but isn't your Z smog inspection exempt? If so, save yourself some $$$ and ditch the smog stuff!!! It will also improve your performance! That's just one mans opinion.

I would eliminate it but the car is all original with only 93,000 show quality and I want to keep it as original as possible.

You would probably be just as well off to go ahead and buy a rebuilt pump if you want to keep it original. MSA has them for about 110 bucks, (with a 50 dollar core charge), which would be much simpler than trying to find parts to rebuild the one you have as I don't know that you would be able to find them. I've never seen rebuild kits or parts for them advertised anywhere so you might have to do a lot of work to rebuild it yourself.

It's either that or find a good used one.