Ok, let me try to assist in clarifying this:

One wire, the THICK one (35RE) goes to the starter. That is easy.
One wire is 6RE, goes to U21 and that is the LH, Fuel injectors and more.
Five wires are 4RE and are:
- Coolant fan #1
- Coolant fan #2
- U15: EZK power, ABS ecu, PSD relay and more
- ABS pump
- PSD pump

So… you might want to connect them one by one. Be careful… can’t warn you enough.