Use better plugs... Base plugs from AC Autolite etc often does not have nickle etc coating as rust protection.
Front side V6 and L4 rust is a major pain rain etc gets to then thru the vents and lid edge. Worse when Recall work removes lid edge rubber.
HEI work w/ most Platinum plugs and only a little more $. Beside lasting longer have anti rust coating on metal.
Cone plugs should not be very tight.
Cone is a sealing area and a "lock washer" sim to cone lug nuts.
Many torque way to tight and causes big problems. Anti seize is lube to tighten and makes that worse for most users.
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
The Ogre's Fiero Cave