I still think that your injectors are ok - as you have said that it runs fine when it's warmed up and during the glow/afterglow period. My car has 276K on original injectors and it runs great. Unfortunately this is no added help to you, I know. I'm just surprised that it's not warmed up enough to start to run smooth when afterglow quits.

BTW, I just did glow plugs, (or should I say had them done) afaik they were original. Fortunately for me the shop had no difficulty extracting them. I had one go south at the beginning of the summer and just lived with it, and then in early fall another went, so starting cold started to be a smoky, noisy affair. It was quite easy to hear the cylinder with the bad plug start to fire after a few seconds, and feel it as well. When two were out it was very rough until those cylinders started firing.

Rgds,
Chris W.
'95 E300D