I crawled underneath today. I learned the break is at the rear of the muffler. The tailpipe is breaking loose from the connection to the muffer.
There is a break in the line between the cat and the muffler. It has a clamp at the break. The clamp and the hangers are very badly rusted -- lost of metal is gone. From what I can see, the replacement tailpipe may need to be two pieces in order to get over the rear axle. Access is good, if only the muffler and tailpipe need replacing. it appears the major problem will be to get the two pieces apart at the break. The pipe can be cut (hacksaw, cutting wheel?) behind the rear axle to get the old parts out.
Anybody made this replacement, and willing to share their experiences?