Rear corner roof repair

[Pascoe92]

My van was converted into a high top camped after it left the factory and unfortunately it was a rather "pooh" job when I've bought the van I decided the high top was coming off but I've found two holes either side of the van in the rear corners which need repair and there is s hold in the middle of the van which was the access into the high top. The issue ive got is I'm unsure on the best option for repairing the two rear corners has anyone repaired these before and got any advise or tips

Cheers pictures below

[Plasticman]

is the hitop going back on ? if yes then add metal as you think fit and weld away, if its not of back on then you need to fabricate very neatly or get a cut to let in, ive done them on one resto thread or the other but dont have the time to search them,sorry
mm