Yes. The exhaust would be different.
You can if the year of the 454 is between the years of 1988 to 1995
yes you can swap the 454 for the 350 its compatible usually any Chevy engine will match in the same vehicle might have to do sum fabrication but in ur situation you should be fine
The frame engine mounts need to be moved and the headers need to swaed with the 350.
motor mounts are different, exhaust won't line up,
It would have more power and use more gas.
Yes. The exhaust is different, and you'll need a bigger radiator.
change ecm also
If the 454 is complete with accessories such as exhaust manifolds, a/c, power steering, alternator, etc., it should be a pretty straightforward swap. Transfer the motor mounts and distributor from the 350. A new exhaust system will likely be needed.
400 turbo
4 and a half ton
What are the differences between a 350 and a 454 engine?
YES they are the same engines.