Power Scaling is from London Power. It doesn't affect tone at all, IMO. Except maybe at very, very low volumes when the speaker element is out of the equation.
Most of the system is in the aluminium box bottom right of thecab. There isn't room in the 5F4 chassis. It's quite tricky to install without experience.
The 5F4 was for a customer, and it's the only Super I've ever heard. Sounded mighty sweet!