no criticsm intended !!!!
i have had to drill one before .
i made a template from a scrap block with crank hole .
then removed flywheel and marked where hole needs to be drilled . then drill hole from g/box side (it is nice, flat surface this side)
it is quite a big hole coz the crank sensor fits in a round plastic holder which i secured from flywheel side as well.
Dont forget to fit the other flywheel as well coz it has cut outs that trigger the crank sensor .
it really isnt a nice job to do , and i was lucky to have a scrap block with the sensor hole as a reference .unfortunately i binned the template.

are you sure you want to go to e.f.i.
i know its not nice to here , but i am on your side