Pickens,
We rig the split bills naked. Putting a skirt on them defeats the purpose of the Splitbill. The Splitbill is a nose down swimming bait. Awsome swimmer!! A nose spring will not work on a split bill you should use copper or monel wire for rigging.
This is how I rig them and some might rig them differently:
The rig itself is simple. It consist of the following for 100lb mono leaders
You can also rig them with short single strand wire leaders.)
One mustad 7732 8/0 hook
One 1/2oz or 3/4oz egg sinker: The 3/4oz sinker will swim a little deeper.
One 12" piece of copper or light test monel wire.
one 100lb heavy wall crimp.
Slide your 100lb sleeve on your mono leader first, Then slide on your hook making sure the tag end of mono runs through the eye of the hook from top to bottom (hook point down is the bottom). Now Slide the weight on the tag end and then push the tag end thru the sleeve. Pull the loop snug but not tight, you will want a little space between the hook and the weight for flexibility. Now crimp the sleeve.
Now take your copper or monel wire and run it thru the eye of the hook about 3" and make a few twist so the wire does not come off. Your rig is now ready.
I like Med Baitmasters ballyhoo for the splitbill. Simply prep the bait by removing the eyes and clipping off the fins near the gills. You will want to break the back of the Ballyhoo in about four or five places from the anal cavity back toward the tail. Be carefull while doing this no not break the skin or remove to many scales. This can be done by pinching the ballyhoo in a few places or doing a series of s-turns. It is very important that the bait is very flexible. I do not remove the poop from the ballyhoo I feel it is just another natural scent in the water (Big Fish Candy)
Next step is to break the bill of the ballyhoo downward leaving the bill about 3/4"-1"in length. When you break the bill downward you will notice the skin under the bill is still attached to the broken off piece of bill. Peel that skin backwards toward the mouth. Now you will see a line on the underside of the bill. Lay the ballyhoo upside down and with a knife split the bill back toward the mouth. I use sissors to split the bill but most folks use a knife.
Now you are ready to rig the ballyhoo on the hook. You want to thread the ballyhoo on the hook to where the weight is underneath the gill plates of ballyhoo Make sure the hook is centered where it exits the belly of the ballyhoo. (A Tip) It is better for the hook to be a little bit closer to the front of the ballyhoo than to far back.
(If the hook is to far back it will create a slight bend or bow in the ballyhoo which will make it spin, this also holds true when rigging a regular ballyhoo rig). Now run the mono up thru the split in the bill and tuck the weight snuggly up underneath the gill plates making sure it is centered. Everything must be centered.
I like to start by putting the long end of the wire thru the eye socket and making one wrap around the weight then two wraps around the bill behind the mono that is thru the splitbill. I then make three or four wraps around the bill in the front of the mono and four wraps back toward the mouth. I then run the wire back thru the eye socket then twist the two ends of wire together and tucking it neatly under the Ballyhoo.
Make sure everything is centered and that the hook is not to far back in the ballyhoo and you should have one hell of a swimming split bill.........Good Luck!! Mark
Catchin' any big King Mackeral ? 
