Palliser:
Hi that_kid. I am sorry to know about your broken foot. Just take it easy. Even thou I have my shield working OK, I still looking for a better out-of-the-shelf board that fits better the design. I am also working on some eagle files to build, at some time, my own design. Remember that for the two transceiver we are going to need 8 pins of the Arduino DUE (CANRX0, CANTX0, CANEN0, CANRS0, CANRX1, CANTX1, CANEN1, CANRS1). For my tests, I didn't use the EN and RS pins. I just connected them to +3.3 and ground respectively.
I've been lurking on this thread since you started it. I would be happy to collaborate on the Eagle files and even fab a board as this fits with my plans. I would be happy to produce a run and share the rate with the good people here. My board would integrate modbus via MAX485 as well with very little extra cost. I also would love even a very beta copy of your sketch if possible.