With a possible timing chain noise going on it has been suggested to me that I should check the condition of the upper chain guide that is mounted on the valve cover. I've got an hour or two of free time today and the rain has let up so I was thinking about pulling the valve cover and checking the guide's condition (so I know whether or not to order it). But I don't have a spare valve cover gasket laying around to replace the old one with, which isn't even that old- I replaced it last summer. Used gasket bond material on the upper half that holds the gasket to the valve cover, no material went onto the engine surface. So how much trouble am I asking for in the short term (say a week or two of reuse)? Either way of my findings the cover is going to have to come back off soon: If guide is bad allowing sloppy chain play going to order a new guide (along with valve cover gasket), and open back up next weekend to replace. Or if guide is good and chain is sloppy going to order a new master link chain (along with valve cover gasket) and replace within the next two or three weekend (allow some time for research). Your thoughts?