I did that swap with the magnum and put a 42RH overdrive behind it with 3.55 sure grip rear end.
The 318B Engine Quest heads are drilled and tapped for LA style intakes if you can get them.
All the front accessories off your 318 fit the Magnum if you prefer to run the OE V belt system.
I chose to stay carbureted because I don’t trust the electronics of EFI, and wanted to be able to get parts anywhere any time.
Everything on my car can be gotten at any parts store in any town on any day.
I have taken my car on trips as long as 17 hours one way, and if an EFI system failed 1000 miles from home, then what?
I do have decades of carb’s experience though, so I get some just don’t want to mess with it.