Welcome Chris. As regards the sealant, do not pull at it. It will continue to ooze for many years so wiil be a regular job if you want to keep the van pristene. When I sold my 2006 van in 2016 I was still tidying areas up each year.
Use an old credit card to cut though the gunge and then roll it back like a child with a ball of snot. With a well dampened white spirit cloth wipe the surface, regularly turning the cloth over to a nice clean bit. When done use a spot of car polish/wax to bring back a shine.

Colin

The problem can be sealant overflow or oozing is excessive. When I collected my new 2017 it was so bad in places that the gutters were blocked and useless. Blobs of sealant were 10 to 12mm in size.

Colin