Just fyi: RoversNorth lists different part #s for a D1 and D2 door.

 

Where'd you see that? I see
LAND ROVER PARTS - ROOF RACK ACCESS LADDER - REAR DISCOVERY I & II

 

That was r.e. the doors being the same.

Rovers North - The Source for Classic Land Rover Parts - DOOR ASSEMBLY-REAR END DISCOVERY I


Rovers North - The Source for Classic Land Rover Parts - DOOR ASSEMBLY - LUGGAGE COMPARTMENT

 

Word of caution after installing a ladder. Be gentle as you are climbing up the ladder. Our rear doors will bend and sag if you get to crazy on the ladder. My Disco came with a ladder, and the rear door leaked pretty bad before I modified the top seal. I'm guessing the PO was not real careful while climbing up the ladder, and bent the top of the door outward slightly...

I know the doors will naturally sag a little, but I'm sure the ladder did not help...