aye, had a look at the sparkfun board, but i have 25 4051's, so best to use them whilst i have them at hand, if you get me.
shit, dont have a schematic at hand of my design. BUT, the multiplexing pdf on the arduino forum is like what i have set-up, such as the z outputs for the second and third 4051, connect to the y0 and y1 of the first 4051, the z output of the first 4051 connected to the analog 0. so on and so forth.
also the the grounds and 5v are connected as is in the pdf.