RepairPal Certified shops can diagnose and repair your 1998 Chevrolet Lumina. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Not a very easy job! You may need to remove some of the items on top of the back valve cover to make some room. If you do decide to replace the spark plugs I would recommend to replace the plug wires while you are at it.