I've got a Cobra with a 428, and I've got a supercharger [Procharger F1R] that is currently on my 540fe tunnelport engine.
After looking at the engine bay on my Cobra I don't see any way that it will fit...........
Here is the supercharged 540fe in my Mustang.
Here is a YT video of a guy with the same supercharger as mine on a 428fe.
[ame]https://www.youtube.com/watch?v=q_IYUeN3TKE[/ame]