I've often read of people fitting these gaskets upside down which blocks the
additional holes in the carb and air-cleaner flanges, and that 'handed' type
of gasket is the only one I have ever seen ... up till now. When replacing
the clutch on a friend's 78 I found these, which can be fitted either way up.
http://www.mgb-stuff.org.uk/images/gaskets.jpg (handed on the left, non-handed
on the right)
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