I got mine finished today. I am sure you could extend it, but when you lay it out and look at it I am not sure you would want to.
And to answer my previous question, drilling the holes were easy. I got a $7 bit from Ace, cordless drill and some Wd40. It did not "smoke" until the end of each drill.
I made 8 holes with no problems. Paint is drying tonight and then I am ready to build a floor!!!