more then likely allen deleted them if you asked him to, or if you told him you were not running the rear 02 sensors, i learned something about these just the other day when i bought a new harness, the bottom picture my harness has 4 of those plugs, which i later found out it was canadien made. the top picture those 02 sensors are used for the front, of a 99 as i have 2 of them practically new that i dont need anymore due to harness difference..if i had to guess for your moms vechicle it would be the top one.. if you need 2 of them i got 2 that i am not using ..