Hi Ludis yep interested in your board. The schematic is of a little peripheral board for P4 ECMs. It plugs onto the edge card test connector of a P4 ECM. Everything fits on a circuit board small enough to fit inside the case of a 1227165. Do we have pcb layout yet..? do you need help with this? And tnx very much for the cyl select info... Mucho appreciated. :peter