I think I have confused you re fron t sprocket removal.
when i say there is not enough play i meant sideways not length ways
I just saw this vid
https://youtu.be/p9lHBeVJuqI
This shows what I am saying. He removes the the big bracket holding the front and rear foot rest and gear shift, then, and then only there is room to move the sprocket and chain in one piece.
just like the vid. lol
I am not getting a new chain just to use the 43 rear.
Billy