The spring fits into
a box under the plate. Its pretty straightforward.
Just make sure you orient the spring same way it was in the OEM plate.
@patrickd018's plate also has adjustments for the spring's tension.
There is also a small set screw for the TH8 sensor to recognize its in seq. mode.
The set screw has same function as the small knob molded into underside of OEM plate.
You may or may not have to fiddle with set screw's adjustment.
I had to screw it down a couple more turns on TH8A than on TH8RS.