20v Silvertop stock ignition timing and fueling maps

[Project D]

I highly doubt you will find anybody with a stock 20v silvertop map.
Stock ECU calculations on the silvertop are based on air flow meter (AFM), so going open ITB means going with a manifold air pressure sensor (MAP) or, even more likely because of the ITB, Aplha-N (TPS based) instead of the AFM, so you would have to start form scratch anyway.
Honestly the hardest part with a standalone ECU is the initial setting.
If you can get past that and once the car start, time to go to the dyno for a proper calibration.