Tallest tire fitment on rear of Scamp

Can anyone confirm that a 28" will for sure fit?

You ever dig into it. I have measured a few times and man it would be awfully close. At this point Im going to have to find a used 275/60-15 just to test fit it.I also may just pop for 275/60-15 nittos. I believe they run smaller at 27-3/4".