High top roof removal on Trident.

Some rust around the top of the  windscreen on my Vw T4 Trident 1992 needs sorting. I'll need to remove the roof to address this properly. Has anyone ever done this and got any tips? All advice appreciated. The van is stored in a barn so canbe left 'roofless' for a while. Im worried about breaking the side trims which cover the join and curl around the screen at the front...they feel fragile.

just come across your post.. so youve probably got sorted now.. anyway there are 5 or 6 screws along the gutter if you look  u will see circle which are little plastic covers or tape covering the screws.. then use a cheese wire to cut away the sika... be careful what you wish for you may unearth more work than u thought. Mine had a leak on O/S corner.. in the end i decided to cut the gutter on the corner at a 45 degree removed about 6 -8 inch piece that wraps around the front and used sika to create a channel within that piece that would divert the water away problem area.. sorted!... but then u sound like you know what your doing if your taking the roof off;)