I think with ofab u need change two wires at ecu ones an 02 n cant remember wat other was.
Wen i put my ofab in i wired it via two yellow relays.
Ran mint for a year daily until i recently stripped it for a reshell.
This time im after a 1.3 shell with no sunroof and will use my full xr3i efi loom and wire it propperly. So my new ofam ecu sits between footwells. Its a doddle if ur already on efi mate