hmmm....

Having driven around a bit tonight with the window down to get a better listen, I now believe I may have an exhaust leak as well. I get what I can ony describe as a light puffing whistle that varies with engine RPM and is non-existent when I get off the gas, but is V-loud when I am heavy on the throttle.

I still have the valve or lifter tapping, but will be trying to flush with frequent oil changes, but will be climbing underneath this weekend to check the exhaust.

 

If you have a little internal clicking, frequent oil changes won't correct if fast enough to prevent internal engine damage.
I would suggest you do an engine flush before your next couple of oil changed so you can break up that crap and get rid of your noise.
Mike