I've recently cured a long term boot leak after I found some split seam sealant at the top of the rear left wing, up near the rear windscreen.
I had previously done all the usual 'fixes'....rear gaskets, sealed in all the chrome attachment points, even removed the rear window to replace all the screen clips.
I also removed, cleaned, and siliconed in both the boot vent panels.
https://photos.app.goo.gl/Bo6BTqb9VVCg4y5L8
https://photos.app.goo.gl/tEyo9DBfW8ArYBac7
https://photos.app.goo.gl/KcdBskkafxffswS88
https://photos.app.goo.gl/h2hVBXf87xvworWcA