This is the beginning of the ECU wiring of my project. What follows are ID's of connectors, followed by the picture of the actual connector itself. This may take a while to straighten everything out. i wanted to at least get the ID's posted. My goal in all of this is to allow the lexus side of the harness to be plug 'n' play with the toyota side of the harness. By splicing matching lexus circuits necessary for operation of the engine/gauges/etc into the identical circuits on the toyota IH1 and IH2 connectors cut from the toyota engine harness, i can make it a lot cleaner in the end, and maintain some degree of sanity in the event diagnosis is ever necessary of the wiring. Also note on the white pages that show the male and female connectors; sometimes instead of a number there will be an "X" or a black dot "*" symbol. The "X" means there is no wire in that cavity. The the black dot "*" (according to my source) says "occupied positions, but not applicable to the system circuit". Here goes.

This is the Toyota connector IH1, male and female sides.
-Pin 22: Black wire, function: Starter control B+
-Pin 14: Black w/Red wire, function: Ignition switched voltage to ignition coils, igniters, and injectors
-Pin 10: Black w/Green wire, function: ECU power (B+) from EFI FUSE
-Pin 16: White w/Red wire, function: B+ voltage from EFI RELAY- powers oxygen sensors, EGR valve, and fuel pump ECU pin 4
-Pin 3: Violet wire, function: MIL/ SES/ Check Engine light (whatever you want to call it)

IH1 connector-- this was cut from the original 3VZ-E engine harness.

This is the toyota connector IH2, male and female sides.
-Pin 14: Yellow w/green wire, function: Temperature gauge signal.
-Pin 11: Yellow w/blue wire, function: Oil pressure gauge signal.
-Pin 20: Black wire, function: Tachometer
-Pin 19: Green w/red wire, function: Speedometer

IH2 connector-- this was also cut from the original 3VZ-E engine harness.

Lexus ECU connector E12 B.

E12 B

Lexus ECU connector E11 A.

E11 A

Lexus EB1: This is one of the two primary connectors on the Lexus side that connect to the Toyota IH1/IH2 connectors in the wire splicing process.
-Pin 4: Black w/yellow wire, function: ECU B+ power from EFI fuse
-Pin 8: Black w/orange wire, function: EFI relay control - on/off

Lexus EB2: this is the second of the two primary Lexus connectors. This one pretty much holds the starter control circuit and the engine sensor/egr positive voltage circuits. Hopefully this one is self-explanatory.

Lexus connector IK1.
-Pin 9: Yellow w/green wire, function: Temp gauge signal
-Pin 20: Yellow w/black wire, function: Oil pressure gauge signal
-Pin 8: Black wire, function: Tachometer
-Pin 7: Blue w/red wire, function: Speedometer

IK1

Lexus connector IK2.
-Pin 9: Blue w/yellow wire, function: MIL/SES/Check Engine light (whatever you want to call it)

IK2

Lexus connector IJ1.
-Pins 3, 7: Black w/orange wire, function: B+ voltage to ignition coils, igniters, and injectors

IJ1

Lexus connector IJ2.
-Pin 11: Black w/orange wire, function: Ignition (B+) voltage from 7.5 Amp 'IGN' fuse to ECU

IJ2

Lexus connector II1.

II1- mine is broken, but seeing as how i don't have the other side, it doesn't really matter.

Lexus connector T12 B. This is one of two connectors that connect to the Lexus traction control ECU. Not used in this swap.

T12 B - This connector is in pretty bad shape on the backside.

Lexus connector T13 A. This is the second of two connectors for the traction control. Not used in this swap.

T13 A - This connector is also in bad shape on the backside.

This is the right lower passenger side kick panel area. The ECU lives down here. The gray connector is the male side of IH1, and the white connector is the male side of IH2. This is where all of the wires will come together and connect the toyota body to the lexus engine harness.
i'll try to post more info on the pins of the connectors that are important. Hopefully by the end of this week, i can post more shots of the lexus and toyota wiring being spliced together and the pins/wires/colors that were spliced.
i discovered during some research that the letter in front of each connector (IH1, EB2, etc) indicates its location in the vehicle. "E" is for the engine compartment, "I" is for the instrument panel and surrounding area, and "B" is for the body and surrounding area.

Toyota connector IH1 pin 14, Black w/Red - connected to Lexus pins 3 and 7, Black w/Orange. The circuit function is ignition coils, igniters, and fuel injectors.

Toyota connector IH1 pin 22, Black - connected to Lexus connector EB2 pin 1, Black. The circuit function is starter control B+.

This is the back of Lexus connector EB2 with the starter wire cut off. Since the harness with this connector comes off the left (driver) side valve cover, i cut it, spliced it, and ran a black wire over to the right side of the firewall and fed it through to the right kick panel with the rest of the wiring.

i will be using this type of butt connector during the swap. i highly recommend these. They are the heat-shrink type. After the butt connection is made, the ends are heated up. They shrink and seal the wire to the butt connector and have proven extremely reliable in other wiring repairs. Once they cool, the connection becomes very solid. The parts department where i work sells these at an insane markup, so i picked up some 25-packs at my local OSH hardware store for just under $10.