Absolutely gutted this evening. Having been right through to the aperture magnetic solenoid component, I found the top FPC connector broken, so couldn't correctly reattached the top ribbon cable.
As a result the top plate dials, such as the mode control and live view button etc don't work.
Had disconnected to avoid breaking the ribbon, as I'd heard it was fragile, but am now unable to connect the ribbon back.
Huge waste of time, and I can't contribute if my aperture solenoid tweaking actually had a positive result
Personally, for anyone else considering this, I don't necessarily think you need to disconnect either the cable or desolder the flash side wires either, to proceed further down and remove the front plate.