I'm starting from scratch. I've completely releaved all the adjuster and all the valves are closed. With the engine at a TDC per the manual I adjust both valves for #1 to .012 per the plaque on the valve cover. As soon as I start to move the engine the intake valve starts to open. By the time I've gone all the way round the valve lash like 3/8".
If you are on TDC of the compression stroke, the intake valve will not open as soon as you turn the engine because that would be the power stroke and the valves will remain closed as the burning of the charge pushes the piston down - sounds like you are TDC on the intake stroke, however you should not set valve clearance at TDC on intake stroke because the vale should already be partly opened - depending on the cam the intake will start to open about 5* or so before TDC.
The dimple on the cam sprocket will be at the top and the dimple will be at the bottom of the crank sprocket when you are at TDC on the compression stroke. I personally prefer to count the chain links
between the dimples - since the links straddle the dimples,
looking at the from of the engine you should have 13 links on the right side and 16 links on the left side
between the links that straddle the dimples. However you get there the pictures earlier tin this thread are what you want to achieve.
Once you have confirmed the correct number of links, then you can adjust the valves and the valve adjustment does not have anything to do with the TDC. I have attached a scan of the small card I carry in my wallet all the time. It is the best way I have found to adjust valves with the minimum turning of the engine - eg, when valve #12 is fully open adjust valve #1, when valve #6 is fully open adjust valve #7, etc. (counting valve from the front so cylinder #1 exhaust valve is valve #1).
Dave