Another crazy Magnum SMPI swap idea. Crank position sensor location.

Yep, that's what I was thinking about on the end of the cam, but maybe a bit smaller in diameter, and more notches.

Hadn't thought about a flat plate like that until I started looking at the Hemi. That would be much easier than machining holes in the barrel of the crank pulley.

My concern with your's is that it will push the crank pulley out of alignment with the rest of the pulleys on a serpentine belt setup. Probably not an issue with a traditional v-belt arrangement (easier to fix the mis-alignment), but seems difficult with serpentine belt. That and I would still have to find a way to mount the sensor in an area that is tight, and far from flat.

One issue with a cam mounted setup is that the plate would need to be adjustable to account for the possibility of degreeing a cam, and I'm not sure how you would get it set as it is behind the cover when the sensor is available to line it up.