Harness and ecm?

[emfh76]

I am swapping an unknown year 5.3 into my 86 c10. I have 1 complete engine with a dbc throttle body and another engine with out a throttle body but came with a blue green pcm. The problem is the harnesses from both engines were cut up in multiple areas and missing connecters. So with the help of lt1swap i have put together a swap harness using the 2003 pin out diagram but it seems there are not provisions in the 2003 pin outs for the iac. So i look on lt1swap and they list pcm numbers that can run the iac and of course the one i have doesnt so should i sell this pcm and pick one up from the yard for a 99 to 02 truck or is there a place i could trade the pcm i have for the one i need? Also i dont have o2 sensors or connectors so im not sure what ones to purchase as there are multiple options for differnt year trucks? This is the last thing i need to complete before i start my swap so any help is appreciated thank you.