I definitely see where you're coming from here. You have several not only valid, but essential points. I should have been a bit more succinct:

In John's partticular situation, his pickups are relatively new and by specific model are wax potted with the beeswax ratio to control the shrinkage. In terms of single coils in general, this should never be presumed as an, "across the board" thing which obviously includes how the polepieces on this particular model of pickups can be manipulated. Trying this remedy with other seemingly similar models may very well require repotting or at worst may outright destroy the pickup's coil.

_________________
You dig?

John,

Yes and yes. The input jack as far as you are concerned for this procedure is irrelevant.

You have to loosen the strings enough to lift the pickguard up and off the guitar which includes all the components underneath the pickguard being able to clear the body and then, being able flip the pickguard over. You will have more room to work if you remove the pickguard and flip it over all from the high E string side, carefully monitoring that the strings don't get caught on the polepieces themselves or the pickups' height adjustment screws.

_________________
You dig?

Lets just say a pickup made using 2 piece Flatwork bobbin (Fender) is different then a pickup made using a plastic bobbin.
There is also a difference between a Slug pole piece and a Magnetic Pole piece.
A slug or a screw goes down through the bobbin ( most are plastic ) to the flat magnet across the bottom.
A two piece flatwork pickup will use 6 magnetic poles ( alnico 5, 3 what ever Fender) held in place by the flatwork. Staggard poles will be different sizes within the flatwork. I have rewound both and never seen a flatwork pickup that had plastic tubes for the magnets between flatwork. Maybe its because they were all old ones.

These things are hard to explan to people most don't realise the different ways they are made using a bar magnet or rod magnets. What it means and how to wind the coil, to pot the pickup, Tap the coil, brush wax it ect.ect.

_________________
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.

Thomas Jefferson