To get an XE running on the bare minimum you will need:

1) Black wire connected to switched live
2) Red wire to permanent live
3) Thick red wire with blue trace to fuel pump
4) Earths on the engine to bodywork

DON'T FORGET the earth for the engine, the ECU picks its earth up from the fuel rail where the black loom box sits.

The red + black (switched live) wires can be found on the right side of the loom just as it exits the black loom box

This might be of some help to you



P.s Nice choice on engine you won't be dissapointed