Look at the rev. changes with the toggle switch off / on ...
Still have to route the wires, but what could this mean exactly?

 

This^^^ Lol

 

thanks ... smh

 

it sounds like the transmission mod if the car is changing gears better. ill be making the same switch tomorrow for my SC400 but don't know if the SC300 is the same thing. follow the wires and if they go to the ECU to a pink wire with a black stripe on it. then it's definitely that. ECU is behind the passenger carpet and behind this black plastic shield

 

I thought it was behind the glove box (??)
Haha; shows what I know ...
You mean it's behind the foot rest? Like against the firewall?
What part of the carpet? (Got a pic?)

 

Ps:
If you watch the video; during "toggle on" it appears that 2nd gear goes up to 70mph, and changes just above 6000RPM, whereas on the first try "toggle off", it changed sooner, at 5-sumtin'.
It also drops differently also, in between shifts.
Watch and see ...

 

sit in the passenger seat, and put your feet on the floor. if you feel against the floor and feel some hard plastic, that's the ecu cover. so technically its not behind the glovebox. its under it. just lift up the carpet a little from that side and you'll see a big black cover. remove that and you'll see the ecu on the left side.

 

It shifted later in 2nd gear.