when you put the knife in do not puncture the bloody intestines or bladder.
my way is to get the coat orft then degut in field. i find it better when they are are warm.
also find coat off first helps. once the coats off you can see what you are doing.

i.e decoat. slit belly. shake bunny upside down, guts fall out. two fingers and pull guts out. only pong should be bunny blood. easily remedied with a wipe on damp grass. then on to next.