crankshaft sensor

I'm trying to replace the crankshaft sensor on 1995 supercharged 3800 is the bolt nomal or reverse thread on the end of the shaft, how do I keep the shaft from turning, anything else I should know?

It's a normal lefty loosy and the only way to get the crank pully bolt off is with an air impact and 15/16 socket. There is a service window on the flywheel gear ring. I used a flat tip screwdriver on the gear ring to prevent the engine from turning. Again a air impact is necessary.