So the foam on the rear wheel well doesn't have to be fully removed to install the butyl, you can simply peel it back out of the way, it just rests on top.
Calibration constitutes making sure they are only extended as much as required
(meaning the bare minimum) in order to grip paper tightly so you can't pull it out
. Here's how I'd do it:
1) Tighten up the ones in the middle all the way in (the ones not
at the tail lights, with no plastic nuts),
2) Check the ones on the tail light are gripping paper tightly so you can't pull it out.
3) If no
, extend them, the same amount of turns and close the door and see if it grips paper. You will have to open/close many times.
4) If yes to step 2,
screw them in and work back outwards until they grip paper at the bare minimum extension.
4) Make sure the plastic nut is against the body of the door (screwed all the way in).
5) After it grips paper, extend the other ones without the plastic nut until they make reasonable grip (sometimes these ones it's easy to slip out paper no matter what you do, so just do it until you see reasonable gripping force.
6) Re-check the other stoppers that they are still gripping paper (i.e. the ones you just adjusted didn't push away the others above the tail lights).
Here's a quick link:
And here's a quick link to the correct time in my video:
I get that my instructions look verbose, I'm sorry, but it's not quite so difficult other than probably consuming 20 minutes of your time. It'll be worth it hopefully once it's done.