what does it mean if my lifters are going? how bad is that for the motor and what will i need to do to fix them?

 

probably means they are wore out. If you Z has high mileage and the oil hasn't been changed regularly then they could be wore out. You will need new lifters. Lifter aren't bad cost wise but labor won't be cheap. If you are for sure you are going need lifters make sure you take it to someone who has worked on a Z before. Goodluck.