Header back parts

I need to replace everything header back, my question is:

Are all 4.0 exhaust routed the same (with the exception of O2 sensor locations)?

Are there any differences say from a 2000 to a 1994 or 1990?

The Renix 4.0 engine and the HO 4.0 have the ports in the head at different elevations, so there must be some difference in length down of the exhaust. It shouldn't be very much. The non-HOs use an EGR and only one O2 sensor (precat). HOs went to two O2 sensors, then in 1999 or 2000 went to the double exhaust manifolds (2 times 3 cylinders) and twin cats, for a total of four O2 sensors. Are you planning to use some used exhaust components? With the beating the exhaust takes, and the way it corrodes, that might be a very short-lived repair.

Thanks Bob for responding....
Well I have beat my cat and flowmaster down like a pancake, and the tube from the header down, is hitting my cross member and skid plate. I was just wondering if it warrented a trip to the junk yard. I have never looked for exhaust parts, but I know what years are at my local yards. I have a 2000 and was not expecting an easy or cheap fix. Good thing I just got is smogged.

Thanks again for the info.