In article ,
"RST Engineering" wrote:
Before you use a PMA plug, get your hands on one and see that your spark
plug wrench is deep enough to get onto the hex. Some plug manufacturers put
the hex all the way down on the bottom, and a standard plug or deep well
socket bottoms out before getting to the twisty part.


This is true with the Autolites, but it's a problem that is easily
solved with a trip to Sears and an extra-long deep socket.



JKG