I recently did the same stuff to my 84 300d. The only door seals that I would puchase are OEM. They are pricey, around 200+ each, but the quality is far superior to all of the others. Mercedes puts fabric into the seals at the wear points so I am confident that these parts will last much longer thatn any of the other brands listed if you plan to keep the car long term. I only replaced the outer wiper seals on my windows. The inner ones are much harder to source and cost lots more, so dont even bother asking mercedes if you are prone to fainting. I attached the loose parts of the door seals with 3M black trim adhesive and it worked very well. the job is pretty straight forward, my only advice is to not stretch the seals as you go around the edge of the door or you will end up with excessive slack where you finish, and grease them up with silicone spray before inserting them. Start at the top corner of each door where there is a 90 degree bend.