I posted the last photo as reference as to how a supercharger could be mounted, doesn't appear to be a Paxton (or at least not the model) that Shelby used.
Shelby used Twin Paxton Superchargers, it should look very similar to this setup.
thgThis photo
This photo gives you some idea as to how a supercharger is mounted.
Picked up the new tool Revell 911, the chassis fits the RSR body very well with minimal modifications.
Modified the interior for a stripped down racer look.
The Fujimi 911R, '73 RS and the Rally all include the same body with no flare at the front and a small flare at the rear. The roll bar is only included in the Rally kit but can be scratch built.
However the '73 RS is the only kit that includes a front bumper/valance that is similar to the Magnus car.