I'm running ms3pro.
I took the air injection pulley and installed a ferrous bolt into it.
I them modified the housing to accept a Hamlin 55505 hall effect sensor.
The benefit of the Hamlin sensor is that it has a built in pull up resistor. This way you don't have to build it in your harness.
There is also a Hamlin 55075 that has a threaded body that might be easier for you to install.
