Glad to see you got a qt tank. Since you have time now, I would grab a sponge filter and seed it w some slush from the bottom of the tank to get bacteria going. That's all you need in a qt tank other than some PVC fittings for fish to hide in. Some people who use the tank transfer method dont even use the filters and just have PVC fittings and powerheads for flow.
Once you have the fish eating in the qt, you can start the tank transfer fairly easily.
Ps remember that since you dt is affected, you have to run it fallow for 72-90 days as mentioned so you have a lot of time to "observe" and treat fish in the qt. don't reintroduce fish to dt early because this would allow the ich that is still present in the dt to survive and one day strike again