Re whether to have wheels off the ground....
I just did my front greasing with wheels off the ground and
grease did seem to come out at the bleed hole area a bit easier. I raised and lowered each wheel a couple of times with a jack,adding grease at up and down positions after the initial greasing.This was to attempt to "spread" grease inside a bit.
I have a compressor so the pneumatic gun makes the job so much easier.
