Wet spark plug threads?
 

Just performed a R&R job on my spark plugs and found that my #1 and #4 plugs are a bit wet around the threads. It kind of looks like a bit of oil too, which has me a bit worried. What would this suggest?

The engine doesn't smoke or consume excessive oil or anything, so it can't be piston rings, right?

The tip/electrodes of all the plugs are a fouled equally. I don't run an O2 sensor, so my car runs a bit rich anyway.

Advice please?

Your issue may be something completely unrelated, but....
Are you using Clewett spark plug wires?

There have been some issues in the past with water and Clewetts - and I'm not sure where things stand at this point.
I searched the forum, but found no definitive answer.