Hi, Tom.... Plug change is pretty straight forward on these.... The usual
stuff about making sure the plug wells are clean goes here.... I check as
many as three times before the plug is all the way out of the head... If
someone has made a habit of using a pressure washer on the engine, small
rocks and dirt can get washed into the well and sometimes get stuck between
the plug hex and the well...

Cylinder heads should be "hand warm" for the least problems.... you'll be
able to tell if the plug is going to give any trouble in about the first
1/8th to 1/4 turn. If it feels like it wants to bind up, spray enough good
penetrant to cover up to the hex of the plug and leave it sit for a while.
We use a product called Aero-Kroil on the 3V troublemakers and this stuff is
great...

For the plugs, I don't think you'll go wrong with the Motorcraft spark
plugs... The motor is a coil on plug ignition system... very
straightforward... and only really requires a plug with platinum centre
electrodes. A quarter inch drive 7mm universal socket will go a long way to
helping get the coil hold down screws out with a minimum of fuss....

While we're making life easier, the vapour management valve is attached to
the heater case.... get that out of the way and it opens up the right side
of the engine quite a bit... I use wrap ties to hold the heater hoses out of
the way a bit, too....

When you install the plugs... they don't need anything on the threads but
they should be properly torqued.... 13 lb/ft is the spec.... don't exceed
that number. A dab of brake caliper/dielectric grease in the end of the coil
boot helps, too....

Every now and again, a coil boot might sieze in the well.... usually a back
one... work carefully with a pick or small screwdriver, some pentrant and an
airhose and you should be safe... get rammy and the boot will rip and make
your life miserble...

HTH

Top postingly yours.....
8^)