Is it doable? I'm sure. Is it a bolt in? Nah. You will probably need to make custom mounts, also you will need an adapter for the transmission. Big block bellhousing is a different pattern, so either an adapted small block trans or or figuring out how to use a big block trans will be necessary. You will need to bypass all computer controls and figure out how to make your gauges work (or go custom). The 9.25 should be fine; I had a 440 in an old Monaco in front of a 9.25 rear.
2003 Ram 1500 QC Hemi Lonestar "Big Red" (Mods list in profile)
2006 Charger R/T "Little Red"
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