I expect this is a stupid question.
How do I fit the right angled steel backing plates for the door handle. ?
With the door card in place you can't get to the backing plate.
I guess you have to do it first with the door laying flat and the door card positioned loosely then "feel" for the threads.
I had to get some 1 1/4" BSW countersunk screws. (Not too long / not too short)!