Carburettor Superchargers

Is there any special fitting process?

As long as its in good condition : has good oil pressure, does not use any oil, and  no crank case breathing, then the process is quite straightforward to many standard or pre-modified.

How is Ignition Controlled?

Ignition control can be from the standard distributor or a mappable one. 

Can the kits be swapped to different engines?

Kits can adapted as your engine is modified further or swapped to a larger or smaller engine with minor changes.