This doesn't look to bad, eh? However, on the inside, a lot of it is just filler and rust.
This is underneath, inside the boot.
Left hand rear, lower.
Cleaned up prior to cutting out rust, and before putting a new plate on.
After new plate and red oxide primer. Customer to skim with filler, then paint.
Right hand foot well / cill, before welding
A closer view.
New plate on outside.
Coated with red oxide primer.