Did you try turning the rail 90° and then slipping it out? It isn't the easiest thing to do, but it can be done.

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Current:
2021 Charger Scat Pack Widebody "Sinabee"
2024 CR-V Hybrid

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1972 280SE 4.5
2018 Durango R/T, 2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
1999 Chrysler 300M - RIP @ 221k