I would assume it will be the same as on a Mk5. Remove standard window and B and C pillar plastic trims. Use rivnut gun to insert threaded inserts into B pillar (2 either side). Fit rubber window seal, bolt B pillar hinge brackets up loosely before inserting rear most bracket tab into slot in C pillar and bolt up. Hopefully the C pillar trim will have a mark to guide you in removing a cutout for the locking mechanism (it does on a Mk4). Nip all the bolts up before refitting the plastics.

Appreciate mine's a Mk4 but I did it start to finish in 45 mins