George, just seen this thread. I'm not sure about the 340 but on the 318 and 360 and possibly all mopars, when you have the dots lined up on the timing chain gears like the pic you posted on page one or two then you are on tdc of #6 cylinder. Top gear should have the timing mark at the top to be on #1 Not sure if you were on tdc #6 in the pic or not. Just trying to help. If it is 180 out you can just drop the distributor in pointing at #6.