This is an old revision of the document!
I'm working on a control surface PCB for MB-SEQ V3.
For now, info on this can be found in this thread: http://www.midibox.org/forum/index.php/topic,11802.0.html
If you want to buy this PCB and optionally the parts to go with it, see this bulk order page: wilba_mb_seq_pcb_bulk_order