Hi all.

 It's 9:30 PM California time and I am trying to finish  resealing an oil
cooler on  a 1971 Bus(I also own a 1983 Westfalia) and unfortunately the
engine stud holding the cooler down has pulled out, stripped its threads.  I
have 8x1.25 helicoils, and various and sundry taps and drills.  But I don't
know what size tap and drill I need to use for the 8mm x  1.25 helicoil.
I've tried the heli-coil web site which is totally worthless, unless someone
knows what drill size "Q" means, or tap size "2087-8".

If there are any night owls with this kind of information handy, I would
greatly appreciate  receiving it.

Thanks,  John