I'm going to try to dissassemble the fuse box (P90 - front power distribution box) at the rear right of the engine compartment.

When hot, my car sometimes won't crank and the problem seems to be the +12V distribution (it's not the starter motor). Although the 12V distibution starts off in the E box (so the problem could be in the E box), I've got a feeling that I'll also need to delve into the engine fuse box as there are quite a few power distribution junctions (X0, X1, X2 and X3) in the fuse box.

How do I take the fuse box apart? As far as I can see, once I've removed the lid, I need to remove 5 Torx screws (4 inside the fuse box, 1 on the external perimeter) and then, while dislodging some plastic tabs, lift up the interior plastic "cover" that sits around the relays.

Presumably the X0-X3 junctions will then be exposed so I can tighten them up?

Thanks!