Hi Rob
Same areas to do as my one,cheak out viva 2300 on restoration
If its front wing your trying to replace,maybe use the arch from this to piece back arches in,but only if its totally gone,
But looks like most of rear sill area should be covered by chrome splash trims after repairs
And some of the NOS sills you can get offered somtimes have a good profile of the arch at the back of sill
Hope this helps
Terry