Hi PaulThat's the bigger one that's the bigger 1 the smaller one is much smaller and uses completely different points setup anything listed as suitable for 4 GTL ducellier will fit
I say chaps .....I bought a tiny electronic ignition kit from these guys: ignitioncarparts.co.uk
Brilliant results! Mine currently uses the points but they no longer spark so do not need adjustment or replacing periodically. However it can be used without points too with a little modification. Kit as I recall was about £40 which seems a lot for an item the size of a small matchbox. However much improved top end speed, starting and economy. They now appear to do replacement electronic dizzys