I was thinking of doing something similar, but with larger cages. We had our boys in an open 4x4 foot pen, but when we got a dog just recently, we had to put them both in a large cage for safety. I would have put them in two separate cages, but every time I've done that, even for a few days, they fight like crazy when they are together again.
Now, I'm weighing my options for more space. One cage I am thinking of buying is about 6 square feet with a second floor, and the second is about 4 square. Anyway - I was thinking about cutting holes on the pans and connecting them with 4"+ PVC pipe, and siliconing to seal.
If you don't need to keep other pets out, you have a lot more lee-way. At one point, we had built a fence from the wire shelving panels around a large area of floor, laid it with plastic mats (those clear hall-runner kind) that we had found at the Dollar General store, and had their smaller cages inside the fence and open so they could hop in and out to eat and sleep.
Also - you can buy cheap linoleum or vinyl flooring remnants for flooring.
I'm not particular good with cutting plastic (or finding it) or wiring cages together either, so you have my sympathy.
Fawn