300D Exhaust assembly- Sealant recommended?

[supercub]

I will be putting my exhaust together with new and almost new mufflers and pipe components. Should I use a sealant in the pipe joints? I will be using the round style clamps.
My center muffler was original MB, production dated 1977! It failed at the weld of the pipe to the muffler body. I think the header pipe was original as well.