You may need a whole lot of exhaust system, if I read you right.

From the head, there is the exhaust header connected to the downpipe. How is that downpipe? OK?

Next is a pipe that connects the downpipe to the catalytic converter (cat), how is that pipe?

The cat is a unit that bolts both front and rear. Note that 1984 and newer have the cat and the pipe to reach the down pipe as one unit. Long piece, and not cheap.

How is the cat? Depending on your emission testing needs, you may or may not need a replacement. I have one sitting loose off a 1979 245DL that's never been tested. Three bolts and a gasket on each end.

After the cat comes what's called the "cat-back" system. Pipe, front muffler, under-axle pipe, back muffler, and tail pipe. Clamps and 4 rubber hangers.

Time spent on piecing together a new part-old part-new part system is a tough learning curve. You will learn why people buy the cat-back new system.

Only better way is to replace the entire system as one piece. I have done this but my parts car was sitting in the driveway next to the car getting the system so it was relatively easy. Three bolts on the cat, four hangers, and drag the whole thing out from under.

Good Luck,

Bob

:>)