Hesston 8400 windrow width

Hi fellas.

I purchased a used Hesston 8400 and its been an education going from a Hesston 6600. I'm having trouble getting the windrows to narrow up. I have the swathing shield raised all the way up. The windrow forming shields all the way in with the extensions extended up to the header and the rear deflector pointing straight down. I'm still getting a flat wide windrow up to 60". I grow straight alfalfa and the crop is fairly heavy. I would appreciate any ideas. Thanks all

Hesston 8400 windrow width