Again, I recommend the switchable Ultimarc's T-Sticks for close to authentic feel with KC.
I have a real KC cab, but on my MAME machine I have each player with one T-Stick and a the first four player buttons in a diamond pattern. It takes a few plays to get used to the idea of pushing the up button instead of jamming a stick upward, but it translates very quickly, and makes your CP useful for lots of other games as well.
It looks something like this: O=T-Stick o=button
o
O o o
o
Another option would be to put a 4 way and a Happs 3-trigger stick, then you could play KC normally and you could get used to using the trigger stick's 7 switches (up, down, left, right, 3 triggers) as buttons for every other game.