Wash your hands first and you should have no problem. My bigger concern is smaller signal tubes (particularly NOS Amperex) where the printing on the tube can easily wipe off and I suspect oil will make that worse; I always try to grab the tube in spots where no printing is located
Can you touch the tubes?
I was talking to someone at the tube store about replacing some KT 150 tubes and he said it was perfectly fine to touch the tubes.
I've always thought you're supposed to handle these things very carefully with white gloves or a microfiber cloth.
Handling them with my fingers makes it easier to pull them out , insert them more securely.
Does it really matter if my fingerprints get on the glass or should I clean them off with a microfiber cloth after I touch them?