Anybody added support to their exhaust system behind the crossmember to help keep the shake/vibration down?

How did you do it; add an extra hanger?

 

Yes on the extra hangers.
Use a hanger with a rubber section so as not to transfer vibrations and still let the exhaust flex slightly.
I like to brush on flat black hi heat stove paint, especially in the seams of a new muffler, to extend the service life.

 

Sorry the pics didn't have a truly good hanger shot, but definately hang it extra.
I like tucked hi as possible. However don't forget heat shields above the Cat and Muff!

 

I've thought about this also since the vibrations from the engine tend to crack the exhaust over time. If you just added in a flex section like this it would probably cut down some of the vibes:




You would weld it into the pipe between the exhaust manifold/header and the main cat converter, it should help isolate engine vibration from the rest of the exhaust. But extra hangers would be a good idea. They sell things like these on Amazon and at parts stores, looks like you just bolt/screw it to the frame somewhere:

 

Cool. I'll have to do one of these things.

Right now my tail pipe is vibrating against my gas tank a little and it's, of course, annoying.

My jeep is an 89 with only 78,000 miles. So it's clean but has a few small adjustments that need to be made before I put that 2" lift on it which will make it look way better.