tclarkson142;106346 wroteAnother useful tool, if you can find one is a Sidchrome 11/16 U-shaped socket for tightening head bolts without having to remove the rocker gear. The Sidchrome part number is 21476 and they were used on Holdens but also fit the B18/20 head bolts.
I borrowed one from a workmate, they are good, but not needed on a b20 with a new elring etc head gasket as they don't need to be re tensioned according to the paperwork.