I have Advance M58 ballasts and was running 6,500K Iwasaki's and switched to 10,000K XM's and love the difference. I don't know anything about your H37 ballasts, if you need new bulbs anyway it's worth a shot.
The yellowy look was driving me crazy.
Here are some pics, the are a bit over exposed especially the first one.
6,500K Iwasaki's
10,000K XM's
