N00B O2 questions, O2 locations, quantity, & replacement Options

[MSKapcala]

I have some questions on the O2 sensor locations in my 1997 GT 2.2L. I ordered 2 new oxygen sensors, the "upstream" and "downstream" (thank you Rock Auto). I googled online and looked for videos, but couldn't find any info on this generation (as far as the sensor locations and how to replace).

I found a picture on the forums here. Is the top one the "upstream" and the lower one the "downstream"? Most of what I see online for other cars or generations of celica say the "downstream" is in the exhaust and under the car. This is why I am confused... Parts websites only list 2 O2 sensors for this car and they look like what is in the picture. I am struggling to find out how to post the picture, but it can be found in this link on this forum - http://www.6gc.net/forums/index.php?showto...sor+replacement


Any help would be greatly appreciated. Thanks!!