Oil Leak In Electronic Ignition

From what l recollect there's an oil seal behind the coil pickup plate and that will be where its coming from.
Carefully mark the exact position of the plate before you remove it,otherwise you will have to re-time the ignition.

 

You have to remove the cover, from what l remember it's a face joint with no gasket, while you're in there it's a good idea to replace the small crankshaft oil supply seal as well,making sure to get it the right way round.
Be sure to carefully mark the points plate before you remove it otherwise you'll have to retime the ignition.