Drilling Holes in Door and Installing Dart GT Trim

So, when I bought my '68 Dart GT, it never had the driver's door trim on it and it was nowhere to be found. I later found out that the door was from a '69 or newer car because the lock was farther forward than the '68 door on the other side. Well, over the years I've acquired the '68 Dart GT driver door trim and now that the car is home, running, and driving... it's really starting to bug me that it's not installed.

Looking at my piece of trim and the passenger door, it seems like the only thing that holds this piece of trim onto the door is 2 nuts. I don't see any provisions for clips in the center. Is it really this easy?

I also have to drill holes into the new door. I really don't want to take it off for fear it won't fit when I put it back on (just my luck). Any tips for drilling holes into the door? Should I drill from the outside going in or vice versa? Should I lie down a layer of painter's tape down before drilling?

Any and all help is appreciated.

Door 1.jpg

Door 2.jpg

Trim 1.jpg

Trim 2.jpg