Popping and stuttering after Efi install and rebuid

Yes tps was calibrated before start up and re calibrated ot just to eliminate that problem. Why would I need kickdown linkage of I'm deciding when to shift gears?
yes the killshot intuctions say to set at 15 degrees btdc with timing locked and then check with timing light at multiple rpm which checked out. Then it says to unlock timing and then it will be "controlled by ecu" which is just 15 degrees at idle then advance almost immediately after acceleration. It says to then check advance timing with timing light. Also checked out.

Could this cause cross fire?> the left side header gasket has a pice of gasket in-between the two center cylinder and the opposing side does not. I'll link a picture

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