Pre-Eagle or Eagle? The 08 older alternators will work. The Eagle alternators won't work that way. They are controlled Waaaay different than the early ones. They are both regulated through the PCM, but, the early ones you can control via the old regulator. Bouchillon has a write up on their site.
You are going to have to send a link because I see nothing over there. I was under the impression that the newer Magnum/ hemi alternators were still isolated field just like 70/ later Mopar back in the day