ok so I'm cutting down a g16B harness to the engine harness for the conversion into a sierra. I'm confident that I have cut it down to the engine harness per the wiring diagram below. I have highlighted what I have in the harness on the floor.

harness as I have it now

I know I have to run an extra fuse for the injectors so I'll build an extra box for that. I'm wondering what the next step is to make it plug and play? do I need to run any wires to the ignition or are the sierra ignition wires used here? ultimately I would like to have everything done so I just need to connect it to the battery and splice in a few wires (fuel pump vss etc.)
cheers for the help, I'll be doing a full write up on how to cut out the engine harness once I get the engine in an working.