The L series uses a stackable valve body for the remotes. You can add up to 3 valves which will have the handles exit on the right side of your seat( should be 3 long slots in front your PTO lever). They are also available with float detents now.
As for doing it yourself, you will need to remove the right rear tire and fender first. Straight in above the axle there is a small plate with 2(I think) bolts that hold the plate on. This plate will be removed and the valve body / bodies are bolted in place. The original plate is then bolted back over the last valve body.
When the L3010 came out you had to buy either a 1, 2, or 3 spool valve body, I started with 1 and had to sell that when I upgraded to 3. Now Kubota offers stackable valves, the only difference being longer bolts depending how many you want, up to a max of 3.
Now, the amount of fluid required to push that big of a cylinder is going to make it slow, any thoughts about a PTO driven pump to supply your splitter.
Hope this was of some help.
Edit- Jay is right on the prices, I have 3 valves, 2 for my TNT with float detents and 1 for my blade angle/offset.If I remember my kit installed was around $1800