How to tighten the doorstop (in the fully open position)

One of my 420 G’ s heavy front doors wont stay open unless the car is parked on a flat surface.
I know what the small part that holds it open looks like, but thought I´d ask before I open the inside of the door. Cleaning and lubing the lock and window regulator, Dynamat and rust proofing is on the list as well, once the door card and plastic protection is removed.
I suppose that removing the 5” little bar will reveal what needs to be tightened or adjusted.
I appreciate all assistance, ss usual.

the door stop needs to be removed simply by removing the pin in on the body, and sliding the arm into the door cavity and out.

You should find 2 metal fingers rivetted to the arm…these “pop” over a metal pressing within the door.

What I found on my 420G drivers door, (and on other vehicles) is that the door only locks into the held open position, with a loud metallic crunch sound…which is the fingers going over the metal to hold the door open…despite trying several things, I was not able to cure this issue

I found a spare arm, but it had the metal fingers broken off

No matter what I fitted, to hold in the open position, I had to put up with a loud clack.
I decided to replace the rubber buffer material…this prevents the clack, but the door wont hold open on a downhill slope.

I cannot explain the situation other than it is also the case with other vehicles on the drivers door, and I theorise it may be due to wear on the internal metal strip, for which their would be no repair that I know of. I could not see any damage

I have it out now. Tried to press the clamps closer to the bar, byusing a vice. This made no difference. I then tried to hit the clamps with a very heavy hammer, against the flat section of the vice. No noticeable difference in action, although the clamps look to be closer, if not touching, the bar.
Perhaps the clamps are of spring hardened steel, and have softened, a bit like sagging rear leaf blades/springs on an XK…:scream:.
I thought of finding another, used one, that might hold the door better.
I donˋt mind the clicking noise. Function before beauty!

doubt if its spring hardened, and I wouldnt hit it with a hammer, I removed a spare and found the fingers had been fractured (from memory the fingers are rivetted to the arm)

Its a bit puzzling…this problem afflicts many vehicles, and I have never heard of a solution, other than a new part.

I suspect the fingers and the steel catch bar wear as matched items, so its hard to get a replacement arm that works…however you have just reminded me where I may have another one to try