Right , i decided to fit one stronger spring for low down advance control just for the test and i need to repair/replace one nylon stop peg as it was damaged ..   Anyway heres how it looks form the inside :   Dizzy shaft and advance/bob weights down in the bottom (one for low down and one for top end advance control):   From top to the bottom - pick up coil , vacuum advance ring , cam with springs :   .. closer look :   Dizzy cam with two springs , this thin one is for low down advance control (i replaced it with stronger thick wire spring now) :   .. and this thick one is for top end advance control :   ....................