The valves are set at TDC on the compression stroke. Intake is .014-.016 and exhaust is .017 - .019 with go nogo gauges or just set at .015 and .018 with straight feeler gauges. That is a cold spec. Pump timing on the CAV pump is generally +1/2 index on the scribe line of the pump, or wherever it was set. I think the Simms should be set at 17 degrees BTDC on a 7700, but I would need to check the book for certain. There should be markings on the timing gears to establish the correct setting, which is not variable. Unless you have a good reason to adjust them, they are probably best left alone. HTH.