Thanks for the input John.
Here in the UK is pretty hard to find high tensile bolts of grade 10-12 that are not black and bolted using Allen keys. I do find it a bit odd, as Allen keys are more likely to round the socket than the normal 6 point hex heads as well.
I'm still investigating where to support the engine before removing the engine mounts. I can put one jack on the transmission side, but to hold the engine I can only see it happening by putting a jack holding the oil sump.
As far as I'm aware, your never supposed to put a jack on the oil sumps because they are not designed to hold weight and tend to bend
Or is it ok in this scenario because the oil sump is only going to hold the engine weight and not the front of the car??