So here is why I took the time to use a straight edge for cutting out the doors. Search for the topic to see how I did that on different sides of the camper and I apologize for having separate posts but any posts I’ve submitted with multiple things (pictures or links) don’t seem to ever show up – just ‘pending moderation’ – whatever that means.
Anyway, the cut is straight and should lead to a nicer looking consistent gap around the door. On this side I used a piece of aluminum stuck to the camper using double sided tape and it worked well. (The aluminum is pulled away and to the left in the picture.)