How the black was on sill and pillar

Take particular notice here.
I you fit your fenders before your black is complete on the pillar your buggered.
You will never get it wright.
Note another great weld from GM Sydney.

The black begins

The sill panel black is best put on pryer to fitting your doors.
The factory painted these with the doors on. That's why the line's where all over the place from original.You will produce much better results with the doors of.

The measurement of 5mm is from the edge of the radius.
See picture below.