i have 4100k kit with hella balast. where i can buy 6000k ultinon bulbs? can i use my balast with 6000k ultinon bulbs without any problems? is the bulb making bluer light or i have to get new balast to get bluer light(9006) tx.

you can use the same ballasts for 6000k bulbs, no problem at all, same light output

you can get bulbs from autolamps-online.com