I have just posted some photos of one of my SYM's that I built up in the 1980's. I have developed several custom designed electronic systems using 6502's. I developed the hardware and software using my SYM's with RAE, disaRAE, BASIC FORTH etc as the development platform. The photos at
http://www.gbronline.com/n5fee/SYM1.htm
show the last SYM based system I built up. I had a couple of earlier systems built around the SYM that evloved into this latest system. I thought some of you might be interested in some of my ideas.