The One eyed beast =)
next time you install a bulb or even do this to the current bulb, is clean the glass part of it with isopropyl alcohol, preferably 91% using a clean lint free cloth. Don't touch the glass at all when installing it or rub it up against crap when installing it.
other than that, i could be the headlight case has lost its seal and moisture is getting in or is contaminated with something inside.
On your Firebird, the lamps are sealed from the factory and don't take any special handling.
Have you changed your bulbs in the last 12-18 months? Are you using Sylvania bulbs? If so, it looks like Sylvania put out a bad series of bulbs.
At one point, I blew a set of Sylvania's after just a couple of months. (both sides) After that, my Sylvania's lasted longer but blew after two years. This is aggravating considering the stock bulbs from the factory lasted me 7 years! My high beams have also never needed replacing.
Other people have had similar issues.
The good news is that Sylvania has a warranty against defective bulbs, if you keep the packaging and receipt. However; the next time I blow one - I'll be looking for a different brand or will be replacing the units with a new system: http://eurolamps.com/eurolamps/camaro_headlights.htm


