Lunati voodoo roller short snout

The short snout cams are specific to the Magnum engines just because the factory eliminated the mechanical fuel pump eccentric provisions and used that extra space for the Magnum timing cover and water pump setup.
If you know for sure you are running an electric fuel pump you should be fine with the short snout cam, just pay attention when the timing chain goes on to make sure the original cam bolt and washer are not bottomed out on the camshaft before tightening the cam gear. It should fit without issue. Use a drop of blue Loctite on the bolt threads during final assembly.

Are you planning to run the stock Magnum timing cover and serpentine belt drive?