All spark plugs are technically pre-gapped. The issues is what they are gapped for??? Plugs are used in a wide array of different products and they can't all be gapped for each specific application from the factory because they don't know what the plug will be used for.
So NEVER assume ANY spark plug is has the proper gap out of the box. ALWAYS check and double check for yourself. While iridium plugs can be fragile if one is ham fisted in their handling of the gapping procedure its not very difficult to properly gap an IR plug is one is careful. The trick is to not put any pressure on the tip inside the insulator. Make all your adjustments on the electrode from the outside. And be very careful not to force a feeler gauge into the gap.
Manual says gap for an NGK CR9 EB for all 1000cc motors is supposed to be .7-.8mm There is no mention of the IR plug so therefore no cross reference.
EDIT: Didn't i send you a link to copies of manuals for the MV?