I suppose it depends where you live. If I could find a rust-free good-bodied 108 with a bad engine that didn't cost me $1000 to ship from Cali & I bought for say $500, it'd be worth doing the engine swap from mine. But in other areas, that isn't the case. Personally if I were going to go through the effort of swapping an engine & trans I'd probably throw in a 5.0 or 5.6 m117 instead and just swap the 4.5 rear in.

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Current:
2021 Charger Scat Pack Widebody "Sinabee"
2018 Durango R/T

Previous:
1972 280SE 4.5
2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
1999 Chrysler 300M - RIP @ 221k