Thanks for the answers.
My car is 81.
My cross measurements are pretty good.
I did some schematics below for the explanations.
I think i solved my problem:
First i tried the roof without the center pins, i didn't obtain more gap.
Secondly I tried with the pins but without the latches and even whith a pressure on the roof the gap was better.
Conclusion, it was the latches which not allow the roof to go backward enough. I filed a litle bit the square holes of the latches (only backward). Now it seem ok, i'm waiting the vinyl cover to see the result.
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