The Judson SP1 kit will fit Healey Sprites (Bugeye, Frogeye and Midget versions), A engined Midgets (not the 1275 engine as the Supercharger cannot cope with the speeds it has to be driven to cope with the larger dispacement). 

It can also be fitted to Morris Minors, Austin A30, A35, A40.  Although a Mini uses the same block, there’s no space in the engine compartment for the Judson.  Instructions are here