the dimensions of the actual led display are 2 x 8.22 inches. No worries there will be plenty this time to fulfill all orders.
About your second question, I'm also going to do a custom adapter board that will allow people to create their own displays by running leads to individual LED's. But this will be released after the kits, there just not enough time to do it all at once. First I need to take care of the actual spectrum analyzer, get this done, manufacture it then take care of addon boards.
As a short inside info, I just got the prototype boards & parts these days, I'm assembling them as we speak and I'll start working on the software.

