Where does the exterior paint end and interior paint start on the door

[johnell]

I am painting my toy for the first time and don't remember where the paint for the outside end and where the interior paint begins. The sealing rubber around the door cab is fine Fawn on the inside and Blue on the outside. On the door outside is blue and inside is fawn but where does the outside color end and the inside color begin. At the edge of the door? There is not seal or gasket around the inside to make up for crooked lines between inside and out paints. The year of the truck is 1966 C10 fleetside where is the edge for painting the door?