Correct ECM for a rebuilt 350?

[88BirdNWOH]

I am swapping out my 305 for a 350 in my Firebird and I am confused on the correct ECM for the 350. The 350 is coming out of a boat and I would like to swap it over to EFI. I currently have the 1228063 ECM in my bird and I have read that most people swap out their 8063 for the 8746. However, the 8746 is designed for the 305 not 350. I have looked at the 1228747 ECMs and those are for 5.7L trucks/vans. Would this ECM work for the 350 and if so, would I need to get a whole new wiring harness for the 1228747?

Right now I am just completely confused on which ECM would work for my 350. Any help would be much appreciated. Thanks.

[Fast355]

I am swapping out my 305 for a 350 in my Firebird and I am confused on the correct ECM for the 350. The 350 is coming out of a boat and I would like to swap it over to EFI. I currently have the 1228063 ECM in my bird and I have read that most people swap out their 8063 for the 8746. However, the 8746 is designed for the 305 not 350. I have looked at the 1228747 ECMs and those are for 5.7L trucks/vans. Would this ECM work for the 350 and if so, would I need to get a whole new wiring harness for the 1228747?

Right now I am just completely confused on which ECM would work for my 350. Any help would be much appreciated. Thanks.

The 8746 came in the 350 powered Civilian Caprice and 9C1 Police Caprice as well as the Buick Roadmaster and some of the Cadillac Fleetwood Broughams.

[EagleMark]

Some of yur confusion may be the fact that any of those ECM will run a 5.0L or 5.7L with the proper chip inside! The chip is varible and marked with a four letter code known as a BCC.

[88BirdNWOH]

What BCC is marked for the 5.7L? Thanks again for the help.

[EagleMark]

There are literaly hundreds..