If anything is leaking replace it. PCV isnt a bad idea. Pretty much any gasket you touch, replace. Timing cover surface should be clean when you put new one back on. It's not a hard job, just take your time and make sure there are no spare parts. Make sure your timing marks (top dead center) line up ahead of time and you're good. It's a fairly primitive engine by modern standards. Only special tool is for turning the cam shaft to line it up, vice grips (not too tight) with a rag over the teeth will do in a pinch. You don't need to take of the driver side chain, passenger side chain leave on the crank (so you dont lose your cam mark) and put a mark where it goes on the cam shaft and put it back on in the same place. That said it is a good time to replace the chains, tensioners and guides, but make sure you look up the procedure, as you dont want the balance shaft to be out of time.