There is such a hodge-podge of headgasket numbers in the Mitsubishi system, perhaps some of the parts houses have bad information..... wouldn't be surprised..... even the dealers get confused.

Tomorrow I'll try an 8mmx1.0 and see if it'll work on the girdle threads, but the 7mm tap was fairly snug. AFAIK, those holes were never touched since the factory built it.... the Diamante SOHC engines didn't use the holes for anything - the oil pickup on the Diamante SOHC has no brace legs..... but maybe they're 8mm and really gunked up with baked oil since they were open.

There is a spec for 7mm - I have the taps and dies and have used them to overtap the water pump rear housing for stripped 6mm threads when installing a new front on an old rear housing.... it makes for an easy solution to a common aluminum problem...... screws are available at Lowes or Home Depot.

Frank