My CEL is on and I am getting a "P0122- 02 sensor CKT slow response, bank 1, sensor 1"

I am going to go ahead and replace that sensor, problem is I have no idea which one it is. Can anyone tell me what bank is #1, and what sensor is #1? Thanks

1998 SVT EO Silver/Midnight Blue 109k Best E/T to date: 15.670 @ 89.10 K&N Blaupunkt 10 disc CD '99 SVT wheels