I know when the show aired on ABC, there was a long and a short version of the opening credits. But when the show is in first run syndication, did they ever use a short version? I feel like I remember seeing a short version for seasons three through six when originally in syndication, but all of the episodes from season three through six which air now, have the full length credits.

I've never seen a short version for the syndicated years. Even during the original ABC run, they sometimes used the short version in prime time.

The real long version of the first season opening credits used on ABC doesn't seem to have been used in many years. On reruns of the show today, it ends,"...That's the way... the traffic flows..., it's.. a.. living," but originally it ended, "...That's the way... the traffic flows, we've... no.. mis... giv...ings... , it's.. a.. living," This longer version might have also been used for the season 1 closing, and the season 2 opening and closing, and the mid-1980s reruns distributed by Golden West, but I'm not sure of that. In season 4, episode 20, "The Howie Show, an instrumental version of the theme (possibly the actual theme's "underdub?") is used as background music near the end of the show, including the "We've no misgivings" part.

Google "1980-81 The Season That Almost Wasn't" to find a Youtube video with the longer theme song.

The longer theme was only used once during the original ABC run, in Season 1.