a very ambitious projectsince you can always buy hardware after the fact, might i suggest not quite investing in the led's right away until you figure out all the hardware?you may also need to look at using multiple microcontrollers and segmenting the display in order to get reasonable refresh rates my guess is that chaining this many drivers together will not yield satisfactory results. you will probably want segments controlled by microcontrollers that at as frame buffers, and microcontrollers dedicated to feeding display information to those frame buffers. you may also find out that the arduino isn't the best platform for this project. you also need to look at total power usage for the led's which will be quite high. what do you want to do with the display? that might provide some more opportunity for feedback. do you also have a budget for this project? i would expect it to run easily into the thousands of dollars range.it's doable though it will just take alot of planning, calculations and cold hard cash do you live near any universities? speaking with seasoned faculty on the subject will answer many questions as well.
Here's a place that does them: http://www.selectricsigns.com/ you can find out how much they cost from them.There is a datasheet there - input power requirments were (IIRC) 12V @ 3A. Not huge, but not insignificant either.As for how to wire it up - modules may be a the right way. One thing I was thinking is that these kind of displays have been around for a long time, going back to the 8080 or Z80 era. It would not have been usual in those days to have many processors. It would probably haev been done with parallel loaded shift registers.It might give a clue as to how to structure a modern design.Also, I seem to remember there being a magazine project some years ago, too. (Probably Elector, but maybe the UK magazine Practical Electronic.Its a good project - certainly gets the brain going.Just found this kit: http://www.hobbytron.com/vk5600g.htmlRuns off a single 18 pin 18C54 PIC - no sign of anyother ICs, so must be multiplexing the whole lot. I doubt this is how it is done on the commercial units.Mike