Replacing Lifters
 

I have a 1986 naturally aspirated 300zx, the engine recently started to tick, I'm almost 100% positive now that it is a lifter. How do you replace the lifters on this engine? I removed the valve cover and I'm not sure where to go from here. Is it necessary to pull the head or is there another layer between the cam and the head? I saw the cam isn't under the valve cover it almost looks as though the cam is between the lifters and pistons, but I'm not sure. Just thought I'd check, don't want to pull the heads if I don't need to.
Thanks.

Instructions are in the Haynes manual. Buy one. Read it.