If it's those shown above, here's all you need to know: http://forums.focaljet.com/mk-i-exte...-pictures.html
And one for getting the high beams to work properly: http://ofoc.ca/hid/step05.html
It's really not all that hard and definitely worth it if he's offering them as a trade. I got my VW plugs off a salvage 200? VW Passat at a junk yard; it was much cheaper than buying new.