Need some diagnosis help. Think I have some dirty and/or failing injectors but want to make sure before I drop the $.

I had a fuel contamination issue I discussed previously with the "coating" inside my tank breaking down. Here's what I did. Replaced tank with good clean used tank - new sending unit with new strainer, flushed and blew out the lines from front to back - pickup and return lines, replaced complete filter housing assembly, and replaced the lift pump since it was weak under load according to the fuel pressure gauge.

Here are my symptoms:

Hard start when cold - this has been going on for a month or so. Turns over strong and it is trying to start but takes a while. Seems to be dumping fuel in because it really belches gray/black smoke when it finally starts. When it's warm - starting is better but not like it has been. Also have to "clear it out" by hitting the throttle as it wants to spit and sputter some after start up.

Has been driving ok around town - throttle response has not been the crispest, but ok.

Took a 4 hr one-way trip to NC this weekend. On Friday - noticed some slight surging and bucking trying to hold steady throttle going down the interstate. Coming home last night - the surging and bucking was much worse. Also noticed the boost gauge going up and down as the engine surged. Does ok under load, but it does not like light steady throttle.

My thought is that I have an injector or mutliple injectors that got trash from the contamination in the tank. I'm thinking they are squirting rather than spraying causing the hard start and the surging. The injectors are 2-3 years old and probably have 30-40K miles on them so they "shouldn't" be worn out. They were new Bosch units from Heath.

2 questions:

Does this sound like an injector issue?

Can they be taken apart and cleaned?

Thanks as always for your input!