back in my junkyard ownership days, i had a 73 powerwagon that originally came with a 318.
was a super easy deal to swap a 440 into it.
when i bought the house i live in back in 1984, i sold the truck to pay for the paperwork required.
the same family still owns it today, and it still retains the same drivetrain i installed all those years ago. i was told the truck still runs like a bear !