From Magnum swap.com
Tips and Tricks
5.9 Magnum “One Piece” Oil Pan Gasket
When using an LA timing cover, it is still possible to use the one piece oil pan gasket from the Magnum engines. Simply use the front ‘U ‘from the timing cover kit—you’ll need one to install the timing cover and water pump anyway–and cut away the corresponding U-shaped piece on the Magnum gasket. A little Rite StuffTM where the rubber gasket meets the new U, and VOILA! Leak free fit!
Scram Speed now sells a
gasket kit specifically for this purpose, using the same gaskets we do.