Has anyone out there modified their 1981 to EFI?

How did it interact with the factory ECM? Can parts of the ECM functions be unhooked and handled by the EFI controls?
The MSD Atom 2900 carries a C.A.R.B. EO # D-722 number and may be legal to install.
Atomic 2900 Atomic EFI Master Kit
Wondering about the Auto trans torque converter lock function and other features not handled by the EFI ECM.