I would take the rear muffler off as it's pretty easy (one clamp and a couple of 13mm hanger bolts) and will give you more room. That said, I don't think that you necessarily have to remove the muffler. I can't remember if '96 has 6 or 8 bolts on the disc; take them out and pry the disc loose. The center slip joint should then allow you to push the rear half of the driveshaft forward enough to get the disc out.

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1983 380SL
1995 C280
1995 S500 coupe
1990 Mazda Miata
2004 Suzuki Hayabusa