help with my rb wiring

[slider78]

whats up guys, I've installed a Rb20det on my sohc 1990 s13 and did all the wiring uder the hood, but now I'm not sure how to wire the one white plug at the ecu to the rb harness, the rb has like 3 white plugs in there, I know where the main relay and start signal go but I know I'm missing something because my ecu in not powered. help would be appreciated, thanks.