I did it the hard, but maybe cheaper way, I bought a couple of 3-1/2" OD by 3-1/2" ID elbows, a 3-1/2" ID x 3-1/2" ID connector and a fistfull of 3-1/2" ID muffler clamps. The elbows were about $30 each, the connector was about $12 and the clamps were a couple of bucks each.
First step was to mark up the old pipe to where I wanted to cut it off. You can see in picture 1-1 where I used a sharpie pen to mark the beginning and end each portion of curved pipe, and a second mark to indicate where the end of new elbow would line up with the existing pipe, along with centerline measurements to make sure the new elbows would be in the proper location to match the existing pipe contours. I used a 3-1/2 radiator hose clamp on the old pipe to make a smooth, even mark.
Pic 1-2 is one elbow, the connector, and the exhaust pipe clamps. After I got the defective pipe cut out, I decided I also had to replace the elbow coming down from the engine, so I made another trip to the parts store for a second elbow and another clamp. The second elbow is not shown in this pic.
After fitting the new parts alongside the old pipe, I remarked the existing J pipe with a red sharpie to indicate the bottom of the socket of the new parts, as shown in pic 1-3. Better to cut off too little than too much, if need be I could cut a little more of the old pipe off to get a better fit.
Pic 1-4 is the old pipe cut off, still haven't cut the second elbow off yet.
Pic 1-5 is the first elbow and connecter in place for a trial fit. This is when I realized I needed to replace the other elbow.
Since I was going through all this work, I decided to wire brush to old pipes down to bare metal and paint with high temp black exhaust paint. Pic 1-6 shows the two pieces of the old J pipe which I reused, prepped for painting.
Pic 1-7 is the completed repair with all parts installed and painted. I think it looks pretty good. If I had to do it all over again, I'd spend the extra money for the flat strap type of pipe clamps instead of the traditional round rod and saddle type of clamp. The flat strap clamps would be much LESS noticeable than he traditional clamps and seal better to boot. I just might change them out anyhow.
Well, did I save any money or not? I figure I've got about $90 dollars in parts and paint, cheaper that the $200+ Saturn stainless steel pipe. Sam Wiener gets $135 plus shipping for a new steel J pipe, so I guess I saved a LITTLE money and had some fun working on the Deuce. Was it worth it, I guess its up to your individual circumstances. At least if I have another rust through it will be in the lower connector, which will be a lot easier and cheaper to fix.