Apart from DSC1 instruction (which did not include a beast due to a last minute hiccup), I 'learned' to gralloch from a BDS DVD by Chris Howard:
3 DVD Stalking Bundle (Free UK P+P)
There are also other videos on Youtube, (I recall a very cunning Irish chap, can't remember his name).
Almost all my gralloch's are suspended in daylight, though I have done one or two with a head torch, and one gralloch on the ground in complete dark by feel only (long story, did not cut myself) !
I use a Victorinox Hunter XS grip. Being able easily to switch between knife and serrated edge for sternum etc, (rather than having two knoives) I find very convenient.
I am still learning and fouled up the latest one a bit by puncturing a full bladder, damnit.
As I don't generally gralloch rabbits (I just take hind legs and backstraps), I cannot really draw a comparison. Suffice to say deer are bigger, bloodier, messier, smellier (especially if gut shot), and thus a little daunting, but all in all not so different.
The only real tutor is go out and shoot one for yourself, expect to be hyperventilating through much of the gralloch, and get as clean a beast as you can into your roe sack.
Richard