^Stupid, pointless, and idiotic... I like it
As for the Cummins swap...
It'd add a TON of front end weight, so you'd need to do a LOT of suspension and a bit of frame work to work it not dump the front end. Next up, a custom wiring harness. Then, custom motor mounts, exhaust, bellhousing adapter, and probably a few other things. That all alone will EASILY eclipse the PITA factor of a relatively drop-in Hemi kit that is pretty all-inclusive and idiot proof, and has great support and lots of people who have done it.
When I was up at Rock Krawler the other day, I heard there's a company very close to offering an LS-swap kit- stay tuned