Bought the injectors and associated parts today online. Should arrive this week and I plan on doing the job next weekend. I'll report back and may even try to write up a DIY on how to do it, especially if it brings a big improvement.

Installed the new injectors last night and there is quite an increase in smoothness, and there seems to be an increase in power (it's hard to know for sure, but it feels that way).

The injector replacement was pretty straightforward, and took me between 2-3 hours, but I am pretty slow and meticulous. Cost was about $200 in parts. It is pretty basic:

-remove air cleaner
-loosen the wiring harness to give more room (3 bolts)
-remove injection lines
-remove injectors with 5mm hex
-install and reverse the above

Buy the sleeves, o-rings, and rubber ring thingy (technical term) and have all this preassembled ahead of time. Only trick thing was to get the new injector into that sleeve with the new rubber ring. Used a deep socket that fit over injector and lightly tapped ino place. You'll see what I mean when you get all the parts and put things together.

I think any owner out there with an M103 with orginal injectors could probably benefit from this work. Smooth as glass now.....

Do you recall the name of the injectors you got? Did you think about cleaning the ones you had? I ran my 240 diesel from 90 to nearly 200 thousand, and never pulled or cleaned the injectors. I just did routine cetane boost conditioner & filter changes + clean fuel. I was always under the impression injectors can go a long ways. The only time I pulled any on the gassers was for head rebuilding.

I just bought them from the ******** in az. Not sure who makes them. These are a bit different from the diesel ones and cannot be rebuilt as far as I can tell. They probably do last a long time, but nozzles do wear. I think it just depends on how far you want to go to get optimal performance and efficiency. The fact that I had one completely plug on me was my motivation. I did notice a much nicer spray pattern with the new ones. Once I get a few more MPG readings, I will be able to report back.

Injectors have been known to be "less than optimal" new out of the box.
If you can have them tested fine.
I have just replaced a single injector out of a new set I purchased around nine months ago - It was opening at too high a pressure.

When doing the injectors make sure you replace the black O ring on the white injector holders.