when installing new rockers how do you know that the rocker is in the middle of the valve stem? (i read somewhere that you put black marker on the end of the stem to show you where your rocker is hitting.) or does this just come into play when you're setting your rockers to the proper valve lash with the feeler gauge? any info would be great! thanks

 

The rocker should be self aligned and easy to adjust, as for setting the lash look for shoebox site and i belive he might have a setp-by-step instruction.