Unfortunately, when the Index marks (T1 & T2) are aligned with the pointer in the hole, the lines on the camshaft sprockets do not align perfectly with the cylinder head. My preference is to align the lines on the sprockets perfectly with the cylinder head rather than have the T1 or T2 marks perfectly aligned with the pointer... The reason they do not line up perfectly is cam chain wear or stretch over a period of time. As your mileage increases, the cam chain stretches, so the lines on the sprockets will move further and further out as well, resulting in retarded valve timing and a noisy engine... not sure if this makes any sense to you, if not, please let me know and I will try to explain it a little further...
For the No.1 Cylinder.
Align these scribed lines perfectly with the cylinder head... This is the Exhaust cam which are on the outside of the cylinder heads on both sides...
This the Inlet cam which are located on the opposite sides of the Exhaust cams, and closest to the throttle bodies....
Using the "T1" index mark for Cylinder 1 & 3, and "T2" for cylinders 2 & 4.... They don't have to be perfectly aligned, as long as the camshaft sprockets are aligned perfectly with the head, as in the photo above...
Using a good feeler gauge, measure between the bottom of the cam lobe and the top of the shim bucket... Exhaust: 0.25 +/- 0.03mm Inlet: 0.16 +/- 0.03mm. Some people use 'inches' to measure clearances, but since all the shims are made and stamped in metric, it makes sense to measure in metric too.... easier to calculate the required replacement shim...
Remember there are 2 exhaust and 2 inlets valves...