What the QEC project is demonstrating, is a step-change in the UK build capability and is significantly in advance of how the US build their CVN.
The level of outfit in the lower blocks - ie beneath the hangar deck (and the islands) is very high, with a significant chunk of the systems commissioned and set to work.
The tricky bit is going to be outfitting the decks between the hangar and flight decks. Because of their shape and division, they're very difficult to outfit - particularly cabling - before they're erected on the ship. The next year is going to see those areas infested with sparkies running and banding cables along, up and across those decks. If that goes well, the rest should be relatively straightforward.
So far so good.