Yes! I'm sorry I jumped the gun, I was thinking the other issue of topping the valves, I slid right by the 16v part.
The dual cam, 4 valve engines are the least sophisticated in their valve adjustment. That means that the engine is built to the adjustment and the point is that there are shims under the cam lobe followers thaty set the valve lash. This should have been done during the assembly of the head. The job, properly done, is done as a part of the valve job as its very possible a valve will have to be topped to use the shim sizes that are available.
If you recieved the head from the machine shop assembled, I would assume that they did this (I would definitely check it). If you gave it to them apart then you will have to do this critical part. If it is already assembled then you need to check your clearnces (if there are any) and calculate the change in shim size, remove the cams and measure the shims, add the difference and order new shims.
Bosch Master, ASE Master, L1
33 years MB technician