Well you don't know if it's the sensor or the actual unit with the harness throwing the code. You'd have to take out the entire unit anyway to replace just the sensor, so why not just replace the entire unit to be on the safe side. I suppose you could just try to take off the sensor, but it's a pain in the ass to work around in that area without taking out the entire unit. 2 bolts vs 3 screws and theres also a harness clip.
I haven't changed it for years, but just look at it and see the work area you have and decide. It's all the way behind the block on top of the tranny housing. Almost right below the intake manifold. If it were my I'd just replace the entire unit anyway and have piece of mind knowing it's oem
