I just removed mine (harmonic balancer bolt) and used an impact gun on the bolt and got it off with little problem (well with a few tries,I own a small compressor)
David
http://FirstGenFirebird.org/show/closeup.mv?CarID=571 If i don't get this car back on the road soon i'm gonna go postal! On a quest for FGF knowledge 1968 Pontiac Firebird Convertible 1969 Oldsmobile Cutlass "S" Convertible *Sold*