Tom, unfortunately thats a difficult thing to track down. My suggestion would be to take one bulb out of each light at a time and see if it persists. Ie, I would start with the front fender markers (the triangle ones) and see if it still does it, since you can drive around without those in, legally. Then maybe the tail light bulbs ( the main red ones). You obviously would need to be careful because the others behind you wont have warning that your stopping.
Check each bulb that is affected when your parking lights are on (not the headlight position on your steering column).
My guess, is that one of your bulbs is not in good shape any more and its shorting out, causing the fuse to blow out. if the wiring im your vx was bad, it would be very intermitten, or every time you turn them on.
It could also be any of the lights on your dash or radio shorting, but less likely because they are surrounded by plastic rather than metal like your exterior bulbs.
Lemme know what you find.
Ps- I thought you sold the vx? (sorry if you already explained this in the sale thread, I generally dont read much into those). if you changed your mind, thats great news!!
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