bkay - if you can find a grandmother's fan block pattern with the strip in, please share it. I have looked and looked.
thimblebug - here is the back.
I have picked the block apart and see that the strip is a curved piece. Once the strip was picked out, I tried the two pinks behind and the light pink wins. I guess I'll trace the strip carefully onto template material and use that to cut out strips for the block because without it the dark blue centers don't fit. I've started sewing the fan blades into pairs and this will make twenty blocks, so that isn't such a terrible amount of cutting curves even if it's a struggle.
Thanks for the tips. I found a tutorial that shows how to attached a curved piece around the top of the fan to square the blocks and I think that's the route I'll take, applique not being my favourite activity.