I've just made 2 wheelspeed input on my V 3.8
If you use only one lambda is the install straight forward. I you (like me) use 2 lambda's is it a bit more tricky.
WS2 is very simple, just use the hole on the first pic with white/blue wire.
WS1 is easy if you dont use lambda 1. In that case just shorten the 2 pads on pic 2 just below the resistors where i have the blue wire. then WS1 logic input will go to the EC18 connector. If, like in my case the EC18 pin is used for lambda 2, then do you have to get connectin on the resistors like I have done. DONT USE the lowest of the 4 holes above (like on older boards. In that case do you connect directly to the ecu without any protection.
If connected correctly are there a protection resistor and diode on the cpu. So it wont fry if you by accident connect +12v on the input.
Remember WS input's are for Hall/logic level 5V. If your sensors are VR, use the VR to hall converter pcba's. These can also divice the frequency, the CPU on the board is a old steam engine, and have limited speed. So WS frequency must be rather low. I'll try to find my test results, but as a guide, do I have 100 pulses per wheel rev, and that need a x8 divider to become usable.