Great tip for engine plumbing and any car wiring for that matter. Noting the "wall fish" mention, an electrician's fish tape is a handy tool to use in the shop as well if you are pulling new wire and don't have the old wire or hose for the first step.
One last mention, "snakeable" remote camera/monitors can really earn their keep for this type of task as well. If you hit an obstruction along a blind path a lot of times you can snake the camera in to see if there is a better route, or if it just needs a bit more of a tug, before you break anything... they are also fairly reasonably priced now too. They aren't just for looking in spark plug holes!
I have even used this trick to install timing chains on motorcycles that use a smaller version of a bicycle chain (and has to go through tunnels) without disassembling the bottom end. The torsion bar sprung DOHC Honda CB450 motor suggests it in right the manual.