I also replaced the electrics box. The other box was ok, but it was quite deep, and meant we couldn't fit the doors on the top cupboards as they caught the things installed in the front of the box. Also, all the toggle switch proved to be a bit of a head and eye risk, sticking out both Shaz and I both caught ourselves on the big metal switches. So the new box is thinner, and all switches are push button and flush as possible. It also means I can fit the doors, if we want them.
In the pics below are how it looks now - its not 100% finished. And its messy as I hate clearing up after myself until I know its all done (or ever, really haha). I've added some detail and a pic of me 'standing' and sitting, to help out a guy on Instagram who's wondering how much room there is inside.
Measurements of note are:
Height added by the high top (vs standard defender roof) 300mm
Bed length 1980mm
Bed width 1460 (at narrowest point)
Height from bed/seat to ceiling 1000mm
Height from ceiling to the top of the side panel (that has the sliding windows in it) ~450mm
Me - I am 5' 9" tall!