Hello, it seems like you are getting lots of answers already, but I'll just let you know what I did on my 300TD, which I gather is similar to the CD. I T-ed the supply heater hose (the one going to the tank) into the hose coming off the block near the oil filter canister, and T-ed the return hose into the heater hose on the passenger side near the front of the block (engine side of that little helper pump). I also ran the hose bundle around the back of the engine (my filter + HE are on the drivers side) and punched through the firewall under the passenger side floor mat. There is a great little space under there to put a 3" or so hole sort of behind and a little inside of the turbo/downpipe (which, btw, I made a heat shield for) The only problem with this routing is the linkage from the accelerator to the throttle assembly. This just requires patience and judiciously placed zip ties. Hope some of this helped. Oh, one other thing, what kind of a system are you installing (components, routing, return, etc)?