Morris Minor Owners Club

the seam between the roof and the body of Primrose (the line under the rear window), is showing several signs of rust and buddles underneath the paint.
how does one go about remedying this rather unsightly rust line?

Grinding back to shiny metal (both sides), welding/brazing/lead loading any holes, levelling (filling) and painting. Simples.

Seriously, it is a major task to eradicate and prevent rust. Most likely there will be other areas that need attention too.

and presumably such measures in that part of the car will require a full respray to get in back to some order of normality.