First obvious question would be why? as you would be giving up a lot of drivability.
Putting a 454 in there would require some specific things but..
If you want to fully strip the TBI wiring out it would be a task removing it from the integrated wiring.
You would also have to have a different sending unit in the tank and add a fuel pump.
Would it be hard, probably not, but going from SBC to BBC will require some specific parts that will add to the change.