1983 Chevy 454 spark plug change.

[NITEHAWK]

Might want to get the appropriate size plug tap and run it down into the threads--carefully--to verify no damaged threads.
McMaster-Carr, Grainger, NAPA, or a knowledgeable friend with the tools.

There are different types of taps for different applications. You want the type with a tapered lead. But do make sure the piston is down on the cyl you are working on.

[MotorPro]

While I tell people never to run a tap in a spark plug hole.....If you really have to be sure to load the tap with grease. It will catch most of the chips an not let them drop in the cylinder. Basically a really bad idea unless there is just no option.

[BFlinn181]

Originally Posted by NITEHAWK

Might want to get the appropriate size plug tap and run it down into the threads--carefully--to verify no damaged threads.
McMaster-Carr, Grainger, NAPA, or a knowledgeable friend with the tools.

There are different types of taps for different applications. You want the type with a tapered lead. But do make sure the piston is down on the cyl you are working on.

I didn't see anything in this thread that suggested bad threads in the head needed cleaning out. It was accessing the plugs and starting them back into the holes, not bad threads.