Bob, I use a 5/16 driver for the glow plug. Don't know if it's different on a P-200.

http://jackmanrob77.gotdns.com/video/glow1.wmv

I put this video together for you just now. Should answer your questions. Sometimes you do get one that blows out in short duration. But most the time they last quite a while.

I usually buy 10 to 20 at a time, and make that purchase every couple years or more. I own 6 or 7 turbines and don't keep track of which one is blowing what, I just always have them on me.