Rusty Gutter

Hi all,

I have an R reg Auto-Sleeper Symphony and have lots of rusty gutter areas with holes. What I would like advice on is removing the black trim that is by the gutter for the whole length of the van. There is, what appears to be, black tape along the black trim. If I remove this tape, would I be able to access screws which hold the trim on? Also, where would I be able to purchase replacement tape.
I love my little camper and used it for weekend camping trips every week before lockdown. It seems to have suffered from being laid up :(
I would be pleased to receive any advice that other members can give,
Thanks in anticipation,
Clare