Is there some good tool to get first upper, third lower bolts on E12 head exhaust and first lower bolt on E121 head intake? As Ben T tald me, original BMW used 12MM studts in those places but all heads that i got were rebored to 13MM. ALLEN or Sears 13MM sockets are not thin enough to do this job. Thanx. Oleg. M3 & 1.5 2002's