Aldon ignitor for 25D distributors with positive earth.
The two best features of the new Ignitor electronic ignition conversion kit is that it fits entirely inside your stock distributor cap! All previous ignition kits utilized an external black box, not the sort of thing you want under the hood of your stock-looking engine compartment! Like the more expensive electronic ignition kits, once you have installed the magnetic trigger and sensor, you will never have to change points ever again! Available for an early 23/25D
(low tension lead clips onto the distributor body) early side and top entry caps.
 
Please note:  For Positive Earth ONLY! 

To adjust the air gap you will need to file one hole in the module mounting lug.
Air gap should be between 0.88mm (0.035") and 1.76 (0.070").
Please Note: DO NOT USE electronic ignition type coil.