JAE;
Did you post pics?.
Would like to see. Am thinking you are drilling through the engine mount tube?.

Thanks

I am also remembering 8mm
What works really well is to purchase just an 8mm ball end allen wrench and cut of the short "L" leg and insert it into a socket.
That gives you an approx 4" long skinny extension beyond your socket.

BTW, only the very first cooling shrouds produced required modification to access the upper left bolt. Any produced in ~2009 and later will require no modification.