Ignition Timing

["Fereday, Chris" <chris.fereday@domain.elided>]

Hi,
Sorry to bother everyone with a question that has probably been asked
several times before...
but I want to check the ignition timing on my MKII Stag (1975). It has a
Lumenition Unit fitted, but I appear to be suffering from 'low down pulling
power'. Its not 'pinking' so I suspect the timing may be retarded. 
Which ignition lead do I connect my strobe gun to (I've seen references to
issues cyl 2 instead of cyl 1) and what timing mark do I 'aim for'?

Your help with this is greatly appreciated

Many Thanks
Chris

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