HI Mike,
I have just done this conversion on a 1.1 bonus and will be firing up at the weekend,
If all goes well, i will share my detailed wiring diagram with you.
I have used an XR3i EFI main harness and an OFAB ecu, with XR3i EFi fuel tank but you can use the S1 tank, Do you have an OFAB Map sensor and Air charge sensor?
Thanks
Rich