thats where the factory 3i ecu sits

sounds like you have a conversion loom to convert a current mfi loom to efi management, that will leave a load of loom in your bay that you didnt want

if you fit a full efi loom you dont need the braided loom you already have, just plug your ecu and map sensor in and away you go, like said you just need to tap into the rear wiring loom for the fuel pump live

also you need to change 1 wire on the edis modue so that your rev counter doesnt read half what it should

can you post a pic of the braided loom you already have?