Ditto on the plenum gasket. There's a whole set of bolts on the underside of the plenum plate, as well as the external bolts holding the intake in place. Yours sounds textbook. Opinions of difficulty vary, but it's easier than the early Magnums since they had the additional hassle of the EGR.
Hughes Engines offers a kit with upgrades that hold the gasket better, has all bolts, etc., in case you are so inclined.