I cannot remove the cartridge from a moen single handle shower faucet. Could someone tell me what the procedure to accomplish this task. I'm an electrician and not a plumber and am afraid I am going to make matters worse.

Clicking on;http://www.moen.com/consumersupport/installation/moen0133/moen0133.cfm
Will get you to a installation guide for replacing a Moen cartridge. You can get a new cartridge from Moen for free call them at 800-289-6636,
Good luck, Tom

Sometimes the O rings swell and the cartridge can be difficult to remove. When that happens you need a Moen cartridge puller. Home Depot about $20.

And here's what a Moen cartridge puller looks like. Good luck, Tom