Good afternoon! I am thinking on doing the "Big 3" upgrade to my electrical system to add more subwoofer / more stable voltage. I do plan to eventually put in a High Output Alternator but thats further down the line. I know i need positive alternator to battery, battery ground, and engine ground. So, are these the engine ground points? I assume it would be a bigger cable. But I didn't immediately notice any other spots. Please let me know if this is correct or not. If not then where would the engine Ground be?
Thanks for reading.

 

There is another ground behind the intake surge tank.
For more info check out https://charm.li/Lexus/2002/RX%20300...d%20Locations/

 

Thanks! I will have to take a closer look tomorrow during the day. Double thanks for including a link to the wiring diagram so I'm not just fumbling around like a ding-dong.