The four wires electrical taped together are the IAC wires. You can see the jumpers in the picture. The long yellow wire above the IAC wires is the JS10 to IGBTIN, then jumper IGN to IGBTOUT. Then at the bottom jumper TachSelect to VRIN. And in the middle of the board TSEL to VROUT.
IMO, ignition setup is by far the hardest thing on the MegaSquirt, fortunately 99% of the setups can be set just like I have it jumpered because the VR circuit can process Hall sensor's just fine.
