I've just done mine

- allow plenty of time (about a day for the two A-pillar and two days for all of the intermediate and falling pillar) - removal and cleaning of the carriers takes ages - I ended up removing the carriers from the car - but the down side was some of the lower self tappers were badly corroded and so I carefully Dremmeled them out with a grinding wheel - cooling the self tappers with water as I went and used pliers and molegrips to get the old screws out.
I got the Sikaflex from E-bay - make sure you are told of the use-by date - Sikaflex has a 12 month shelf life (I used black Sikaflex 221 I think).
You'll only need one tube - it goes a long way - beware the Sikaflex eventually cures in the tube once opened - apparently it reacts to moisture in the air - so do all your jobs over a few days and store in a cool place - save you buying another tube.
Sikalfex takes overnight to cure, wear plastic/rubber surgical-type gloves (eg from screwfix) and old clothes - the Sikaflex is very sticky when un-cured and gets everywhere - if you need to remove it from your skin or anywhere else - meths works - also good for degreasing the carriers.
The intermediate and falling pillar seals are held in by a phillips-headed bolt and a captive nut which is held in the carrier - if you look carefully at the carrier from inside the car there are two cutouts on each of the black metal carrier immediately behind the rubber seal - that is where the nut is - a philips screwdriver gently pushed against the inner side of the seal will reveal the bolt
I found the A-pillar seals were pretty easy to get right - intermediate and falling pillar were real pigs to get right because you have to get the edges to line up properly - they still ain't right - trouble is youu have to adjust them a bit and then sikaflex them on place - leave it to cure and then adjust again

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Now I am on the lookout for a header rail seal - being as I discovered than whoever did the roof - cut off the back of the seal to ease fitting - (wondered why it was twisted and looked crap - only £200 odd from SJ's

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