Interesting that the smoke isn't coming from the dead cylinder.
Personally, I wouldn't be spending tons of money/effort trying to fix the smoke with a dead cylinder, because fixing the dead cylinder will probably require pulling the motor (unless it is just a mis-adjusted valve hanging open). However, it is possible to run around on 7.5 cylinders (I did for almost 10,000 miles after a glowplug went through my #1 cylinder and nuked the exhaust valve seats). If you are going to run it that way until you save up for new hard parts, then yeah, we can address the smoke first.
Have you taken a clean rag and held it over the exhaust for a while? It will absorb some of whatever the smoke is (especially as thick as your smoke is). Once it has absorbed the stuff, you can take your time to smell it and feel it. Hopefully that will point you in the right direction (coolant vs. diesel vs. oil).
There is always the possibility that you had a bad injector, then your new injectors had one or more bad as well. I am not familiar with Injectors Direct, but it looks like they sell refurbished or remanufactured injectors. I am not sure if their remanufactured injectors are any good, but it isn't possible for anyone to successfully refurbish an LB7 injector. If you got those, that is probably your problem. Specifically, you just bought someone else's problem. Why would anyone remove a working injector? Think about where they get their cores... from customers with problems already.