Thule omnistep rocker switch

The original Thule Omnistep operating switch on our beloved 2004 Ace Milano RV has finally packed in leaving the double step inoperable, and we simply cannot source a direct replacement switch. That defunct switch has five in-line terminals with numbers two and four bridged with a soldered wire. However, the latest Thule replacement rocker switch has a different five-terminal configuration with numbers two and three at right angles to the other three (see first two photos for switch detail).

I am unsure which of the four colour-coded wires (see third photo) attaches to which terminal, and whether or not a soldered bridging wire is still required.

Could someone out there whose RV has the modern switch, possibly check the back of it by easing off the surround then unscrewing the four simple stub screws, and advise me (perhaps via a photograph) of the wiring layout required? Many thanks in anticipation!