The tubes have to come off to replace the DPF, so I blow them out then. I'm not exactly sure what you are asking here. Are you familiar with the layout of the exhaust system on the CJAA?
They are quite an albatross of tubes and sensors.
The first pic, is the assembly as it is removed from the car, the second pic is the space it was taken from, the low pressure EGR valve and cooler and bottom side of the turbocharger assembly is mostly what you see. But you can also see the tube going to the EGR differential pressure sensor, down low and left right near the transmission case... goes up, turns, wrapped past the turbo, and up some more and goes to a little hose.
That hose is what connects to the EGR pressure sensor, which I remove (along with the DPF pressure sensor) that can both be seen in the first pic. The DPF sensor is the one dangling by the shop floor off to the left.
All of the sensors in that pic, as well as the one that has already been removed, both the pressure sensors, and the pipe Y-assembly that is attached to the DPF assembly, all get removed and transferred over to the new DPF. I don't have any pics of them taken apart, but I can get some the next one I do (likely won't be long, I see these constantly).