sorry guys but I've been battling COVID for the last 7 days so my thoughts have been a little choppy.
I'm stuck on the fact that 1 mechanic gets good compression on cylinder 1 and another shows only 65lbs. So I worked through the process in my head trying to account for this.
For the benefit of the OP I'll run through the process.
So the head gets bolted down, camshafts installed, timing chain, distributor, spark plugs and valve cover. Or there abouts.
At this point the lower intake is installed. I always wad up paper towels and stuff the runners so nothing can fall inside as the intake holes are facing straight up. If something were to fall into a runner it would likely disappear out of sight.
The next step is to wrangle the engine harness back into place which requires threading it through the lower intake and then plugging it into all the injectors and sensors along the side of the block.
I think something might have fallen down the #1 intake runner and is banging around the back side of the valve. Somethings holding the valve open slightly. Maybe an M8 flat washer.
I would pull the upper intake and go fishing with a magnet. It's a simple job and you might hit pay dirt.
That's a great suggestion. There's plenty of things that could go down the intake, and not make it past a valve straight away
Skip the mobile phone endoscope though, go get one from Harbour Freight or similar