Roof Carrier Recommendation?

Does anybody have any experience with which type(s) of ski boxes would fit on the factory 2003 Montana rack? The crossbars are slightly concave so I'm not sure if there are any of the wider style boxes that would fit properly. Any comments or recommendations would be greatly appreciated. THANKS!

I haven't used a ski box but I have a 19cubic foot carrier I bought at Sears. It's called X-Cargo, I purchased a mounting kit that has "U" bolts and thumb screws. I had to drill holes in the bottom of the carrier but the U bolts work great. The box is almost as wide as the roof rack and I have not had any problems driving on long or short trips with the box full or empty. I live in Western PA. and have seen many Montana's running around with ski carriers on them. You may want to stop at a Sears automotive center, if their any good they should have one in stock and should let you test fit on your van before you buy.
Good Luck, and welcome to the forum, you will find lots of great info. on this site.
Enjoy the forum,
Dan