Glad you found something to keep your interest instead of just dropping the whole project. I think the G3 swap is going to cost you a lot of time and re-work, but better that than seeing it listed for sale in another year. Get'er done!
Honestly, only thing holding me back from doing something similar is funds. I loved my Challenger and would love to drop a similar motor in my Duster. Hard not to daydream about an Eagle with a 6.4 cam, I don't even need a full 6.4.