Yes, I had duals run on my 1985 EC about 5 years ago and still in great shape. I had the head pipes from exhaust manifolds to mufflers (with catalysts in between) custom bent in two inch tubing. Then I used 1979 Z28 mufflers with 2" inlets and outlets (these mufflers have a great sound). For tailpipes I used 1987 Monte SS tailpipes and then put 12 (or 16) inch chrome extensions on the end as this makes up for the shorter tailpipes. Sounds great, looks great and lots of additional power.
the only way to fly . i have duals on my 86, 2 1/4 in from manifold to tailpipe.i have the long quiet mufflers on mine,after 35 yrs of raiseing kids i am ready for some quiet.my exhaust mimics the factory y pipe path then moves to thier respective sides of the car. no clearance issues and no double hump crossmember