The bottom part is not going to be that difficuilt to add. I have a guide for every part of it:
Laserschwert already did most of the monkey, the rest is much easier. I don't know how much more is on the original painting - but if the sketch is anything to go by not much.
Don't forget I filled in the KIXX MI2 scan as well... this is what it looked like after blending it with the bottom of the LEC Box:
And it came out brilliantly!