Hell, you have already done most of the stuff! You will like the injectors. It sounds like you may have gotten the "Power Wagon" injectors.
You still need to time the pump and tweak it a little.
The injectors are easy to change. The #6 can be a little tough to get out sometimes due to corrosion on the injector body. You can make a small slide puller by getting a metric nut that fits the threads on the top of the injector. Get a 6" or so long bolt that fits the bolt, slide a large socket on it and then thread the bolt into the nut on the top of the injector. will only take a couple of small "taps" with the socket to get the injectors out.
You can get them out without taking the fuel lines loose from the pump. You will need to pull the valve covers off of 2 and 5 to make a little room. Be careful and don't kink or bend the lines.
Clean the injector bores good. Cummings makes a special brush for this but I used a shotgun cleaning brush. Don't remember the gauge, but it seems like 16 gauge. Check the size bore and you can figure it out.
Reconnect the lines and try to start it up. Will run rough for a minute or so then level out. Some guys have to bleed the lines but the couple of times I did it, the truck started right up after a few revs with the starter.
Hope this helps