Pull the reservoir cover off, pull the clutch lever in, tie it in the fully depressed position. Bungie cord, zip tie, what ever. Leave it that way, with the reservoir cover off, over night.
Then see if the problem persists. The small volume of the clutch reservoir can make it very difficult to get a complete bleed. Like you, I did everything, including the banjo bolt trick, but it still felt slightly off at the lever. Doing what I suggest, (another forum member suggested it to me), did the trick.
The symptoms you describe essentially suggest one of two issues. Incomplete disengagement, (most likely due to air in the system), or stuck plates. Stuck plates have occurred, but rarely on a bike that was fine before doing the basket swap. Usually on left over bikes that sat at a dealer for a long time before being sold. The new places get stuck together from lack of use and little oil circulation during the time the bike sits.
Hope that helps.