Hi Rich.
I think you are correct in that the SPAD VII did not have the vented fuel filler to the right of the cockpit.
All of the photographs I've seen have no filler at that location.
The main fuel tank was placed in the fuselage under the pilot's seat, and an auxiliary tank in the upper wing, which was filled through a filler cap on the wing (next to the cooling system expansion tank /filler).
This tank supplied fuel through a pipe inside the central fairing forward from the cockpit.
The fuel tanks had a total capacity of 135 liters.
Unfortunately there's not much detailed information of the SPAD VII cockpit or fuel system.
As you pointed out the SPAD XIII has the vented fuel filler cap.
If you use the following link, it'll take you to a 360 degree scroll around the cockpit of a SPAD XIII (using your mouse).
There you can clearly see the fuel filler and pipe leading to the engine fuel pump.
I'm guessing the pipe had a T-piece connection to the main fuel tank.
Along side the pipe you can see the oil tank and its filler cap and associated pipe work.
http://www.nmusafvirtualtour.com/cockpits/EY_tour/EY-7.htmlAs the SPAD VII doesn't appear to have such a visible fuel filler, I'm guessing Roden based there detail on the SPAD XIII cockpit detail.
Including what they thought was a combined fuel pipe and oil tank filler??
I suppose it's possible the main fuel tank on the SPAD VII was filled from fuel supplied through pipework from filling the upper wing auxiliary tank?
If it was me I'd discard that part as being suspect SPAD XIII.
It's your call though,
Mike