Above link is queued to 2 minutes into the vid - the start of the interesting stuff.
body: 1949 Packard
Rear end with leafs: out of 2007 Chevy Duramax chassis short school bus
Chassis: 1996 Dodge 3/4 Ton 5.9 diesel truck
motor: 454 out of a motorhome
The general YT vid (for a quick picture of it):
49 Rescue Pig & Garage Bound LLC Shop Visit