My "kit" is a 4" fixed blade knife, a tiny little gerber hatchet (for the pelvis... I know, I could use a knife, but this is way easier), and a pair of rubber gloves. When I hunt with my FIL, I also carry a 1 gallon zip lock bag (he likes liver, me? not so much). In the truck I leave a 5 gallon bucket for rinsing.
OH, somebody gave me a "butt-out" for Christmas as a jokea few years ago
. I haven't tried it yet.
-nosualc
ps - My knife is a Knives of Alaska fixed blade (it was a gift a few years ago; they don't make the same model anymore), but I really like the Gerber Gator and Buck Vanguard.