When changing my oxygen senors on my 1999 chevy suburban 2500 7.4 lt where is bank 1 sensor 2 located at?

Bank 1 is usually on the side of the engine with cylinder 1. It's the one that's after the catalytic converter. Sensor 2 is also known as the downstream sensor. It senses the efficiency of the converter. If you have a code scanner, you could unplug it and see which code pops up.