WANTED M7 x 0.75, M7 x 1.00 bolts

No just steel torx head bolts.

I'm a builder, it's generally hammer, bigger hammer and then JCB.

 

just a thought stainless ones on a small ali thread without much meat might not be good ?

 

found this if it helps??

 

Me too, but in this case i would probably of resorted to gripfill

 

Helicoils usually come in diameter increments, as in 1d being 6mm long and 3d being 18 mm long for M6, we get them from Cromwells industrial supplies, would recommend genuine helicoil as they compress more when fitting, and therefore less likely to move.

Answer to your question, yes you can fit more than one per hole if needed.