The headlights on my 2001 XJ are dangerously dim. I bought the 200mm Euro H4 kit & the wiring harness. I got the lights today but have yet to receive the harness. Do you think I could go ahead and install the lamps for a couple of days with the stock wiring and not have any issues?

 

I doubt you would have any issues but why don't you just wait until you get the harness? You're going to have to pull the headlights out again when you install it.

 

Good point. But I have to drive to work @ 4:00 am tomorrow. & last night driving home in the dark was way too dangerous.
And now that I installed them everything works great BUT when I shut the car off, the lights stayed on until I re engaged the starter then they turned off. I am more than a little concerned about my drive to work.

 

You will be fine. I put in my H4's about 6 months ago and still haven't put in my new wire harness and I haven't had a single problem.