Rabbit Igloo Rabbit Cage Conversion/Bedding?

Rabbit Cage Conversion/Bedding? - rabbit igloo

I have a fairly large rabbit weighing two to four pounds.
I will be the conversion of his cage a little. This is your cage:
http://images.hayneedle.com/mgen/master ...
I take the metal grid in the middle, because I recently trained in the trash, and I do not need to their cages every 4 days to clean. Then I'll put a few rungs in the plastic base to avoid a crash, but I'm afraid you do not have enough space. He has just enough. There is a plastic igloo rabbit, a bed of sand, his ball out of hay, food bowl and water bottle. Only in this cage for a few months, because I work in a shed outside for him. Could something on the side in the center that has a little more that (but) without network:
http://ecx.images-amazon.com/images/I/41 ...
it would be a good idea?

My other question is what the beds would be set well below it. I currently use recycled paper towels for a bed of sand, but readyand expensive, a nd I know that I think of cedar and pine (?) are not good for them. What a cheap, healthy bedding for my rabbit? I did not spend much money for a month.