Which cylinder is number 5? Engine misfire

About a month ago I pulled my car from the driveway into the garage. The next morning when I started the car it the engine was shaking like crazy and the check engine light came on.

I read/reset the code with my cheapie code reader and it was "cylinder 5 misfire". The next time I started the car it ran fine.

Last night I pulled the car in from the driveway and into the garage. My wife started it this morning and she said it was running rough/shaking again. This time it corrected itself after a few seconds and no check engine light came on.

I'm assuming I probably either have a bad plug, bad coil, or leaky gasket that is fouling the plug. I tempted to pull the plug and take a peak. Would number 5 cylinder be the second from the front of the car, or the rear (firewall side)?