I have a 1976 Chevy K5 Blazer that I just did a head job on it. I need to know what's the easiest way to adjust the rocker arms if I can't get the crank to turn?

 

If I'm not mistake, you can only adjust the rocker arms while the engine is running. There is a pre-set torque to them before starting the engine up but they must be set while the eninge is running.

And if you can't get the engine to turn over, you have bigger problems than setting the valve lash.

 

I'll second the "bigger problems" comment.

You can set them without the engine running, but you must rotate the engine to be able to set the initial tension on the lifter while it is on the base circle of the cam.