So rev hang is basically the same system as the go pedel to the floor shifting, the ECM holds the rpm's stable so the engine doesn't over rev while shifting
I would stick with mechanical means as much as possible. Use a shop vac attached to the inlet side to create as much reverse airflow as possible, invert it to let gravity help move any particles, and then use a low-pressure air gun at the exit to agitate the airflow as much as possible.I know there's oil in it from the pcv system and from when the turbo blew. When I pulled the the pipe off the turbo there was oil in it. My biggest concern is getting all the metel out.