I'm producing a TV spot, to be finished in standard def. We want to deliver it in 16x9 format, so that it fills a 16x9 TV. So, we are going to produce a 16x9 Anamorphic master. My question is: Do any TV stations accept spots as 16x9 anamorphic, in standard def? If so, is there a way to encode them so they are letterboxed if being watched on a 4x3 TV? OR do we have to produce two versions, letterboxed and anamorphic? Any suggestions?