Manufacturer says the linkage is not correct for the left side valves to open quicker and fuller than the right side, but I'm not sure if it came that way years ago from the manufacturer or if someone modified the linkage arm when building the engine. He did say the cross linkage is correct to be slightly bent so it travels under the rails when pressing the throttle. But anyway I have to take things apart and send him the valves & linkage so he can update everything so I need to stick my head in there and see how to disconnect things. But the funny thing is that I adjusted all the valves to his specs at rest (.002 inch) and figured to start the car and see how things run on idle with valves still resting and the engine raced to about 2,500 RPM and backfired, wife crapping the pants in the livingroom. I assume maybe that was due to the Speed-Pro ECU still programed back in the day with dirty valves and now with clean valves and the .002 correct adjustment now things don't match up with the ECU. That is unless something else is still wrong. Finally found my compression gauge in the attic, so I'm going to get to that first. So glad I'm retired to mess with it on and off, but I really would like to drive!