problems with 97 fog light rewire

I re-wired my fog lights to be able to turn on independently of the headlights by using these instructions from vqpower.com. The mod is cool but the foglight bulb closest to the new connection to the parking light(passenger side) keeps burning out in about a week after replacement. What could be causing this and is there something I can do to correct the problem? Thanks

http://www.vqpower.com/v2/modules.php?name=Content&pa=showpage&pid=6

...bulb closest to the new connection ... keeps burning out ...

Why do bulbs burn? (some of these apply in this q)

*Bulb:
- age
- poor quality:
~mfg problem
~seller mishandling (dropped?)
~buyer mishandling (dropped, touched lens)
- bulb wrong rating: 'northern' alternator charge voltage is higher, some bulb producers manufacture two kinds bulbs with diff ratings.
- loose bulb/lamp installation: vibration kills

*Supply:
- over/spiky voltage, alt regulator and/or rectifier bad
- bad sw/relay/connection in supply -or- gnd wire ('sparking' during connection or droppin continously on/off)
- surge in a pair: during connection the pair causes a surge voltage in the 'slower starting lamp' (two lamps are never exact equal). In some pair-settings (!?) this causes one lamp failure. As one has burned, the other one will not: as paired, always one burns very soon, second lives 'forever'. Applies to home 120/240VAC bulbs also... (car: install separate relays, and/or spike killer diodes)

Two foglamps, two relays: http://www.cardomain.com/ride/748507/11

About fog light setting: Check local regulations how/which lamps are allowed... here this would not pass insepction.

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