The hardblock itself is locked to a particular quad so yes it is technically locked to the pin set in that quad but the core it self should show what is capable or not. You may have to go into advanced mode settings to do it. Check the PCI-E Core product guide PG054. In particular, see table 2-5 on page 11. It shows all available integrated PCI-E blocks in a particular 7-series device. Also, check the PCI-E core itself. If the core does not allow you to select another pin from a different quad then it is not supported. If it does then you are set.
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