Why not just convert to an EFI tophat type injection. Might take some fabrication, but it would be way cool and you would probably get it to run alot better on the street. Couple of sensors from the junkyard, a new WB sensor, Genboard V3.2, some time building a harness, and you are on your way. If you are injecting before the blower, it should tune just like an NA engine.
If i had the extra moneys i want the BDS EFI system,$$$ To much time to fab time for me to set one up and get dialed in. The old mechanical systems look a lot cleaner under the hood and used equipment can be found everywhere at real good prices. Thanks for idea, Did you get your bottom end back together? Thanks, Scott