http://vfaq.com/mods/zeitronix_wideband_vfaq.html
From here these are instructions for the Kavlico (AEM 3.5 bar) boost sensor wiring to the ZT-2 harness.
1. Strip ~5mm of plastic jacket from the three wires coming off the boost sensor and the brown, light brown, and yellow wires from the ZT-2 harness. Here are the corresponding wires:
Kavlico black wire to the ZT-2's brown wire
Kavlico green wire to the ZT-2's light brown wire
Kavlico red wire to the ZT-2's yellow wire
2. Slide a section of shrink tube over the wires on the ZT-2 harness. Twist corresponding wires together (or alternately just slide them into each other) from the boost sensor/ZT-2 and solder. Heat up that shrink tube and cover all those new connections. Enjoy your medical-grade-accurate boost readings from the ZT-2!
enjoy