what is the best method to adjust the valves after a valve job?

Follow the instructions in the Factory Service Manual.

The determination of the initial 'zero lash' point is critical before tightening the nut above the rocker.

[This message has been edited by olejoedad (edited 06-02-2022).]

As Joe has stated, finding "zero lash" is critical. I suspect a lot of people screw this up. I explained how I went through the process of setting valve lash on a 2,8 Here.

Easiest way and most precise way. Mark balancer with chalk into 4 equal 1/4 turn segments. With plugs removed and all rockers in place but loose, put engine on TDC timing mark. Take out all the slack on each push rod by moving them up and down with your fingers until no more movement is felt. Rotate engine 1/4 turn and do this again. Then again at another 1/4 turn continuing to take the slack out on each cylinder on each 1/4 turn for two complete rotations of the crankshaft. Now go to each rocker bolt and tighten each 1 1/2 turns. Done

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