This thread really helped me out; I recently bought a '72 240 off of eBay. It was great but the drivers side door had to be slammed to the point of concern or it would not fully latch. From inside the car it was very difficult.
After finding this thread in a bout of restlessness last night; I went to Lowes and bought a 36" piece of 3/8" PEX pipe. PEX is made from polyethylene and is pretty similar to nylon in hardness and low friction.
I trimmed a 3/8" piece off and made one cut along the side. After submerging it in boiling water for a few minutes, I formed it around the 1/2" handle of the x-acto I used to cut it with.
It snapped right on the contact lobe of the door latch.
The door closes almost without effort now.
15 minutes for both doors and $1.60 in materials.
No grinding.
