The MPC was in between the MC-1 and the MXC (http://web.archive.org/web/20040217022455/http://www.adadepot.com:80/adagear/gearpages/pedals/ADA-MPC.htm), so MC-1 came out with MP-1 originally, MPC has much the same functionality to MC-1 but a better footprint (2 rows of buttons so no so wide), the MXC is basically the MPC but with CC (pedal and switch) options added.
I found some perfect 9V AC adapters (wall warts) from Jaycar in Australia, Model KSLFB0900055W1AU, Input 100-240V ~ 50/60Hz 0.15A, Output 9.0V --- 0.55A, you should be able to source something equivalent in the US. They come with a range of tips and one of them was just perfect for my MXC pedals.
Unfortunately, the wayback time machine link above to the old depot site doesn't include a manual, pics or schematic (the links don't work
), but if anyone has the CD that Jur put together way back when, it should be on there. My guess is that the MXC manual is the same as the MPC manual (functions options) except for the CC additions (which came with MP-2/MXC).