Corsa is the only exhaust I’ve used that kills all drone. They have a cross over system in a 3” designed for 1998-2002 camaro and firebird.
https://www.summitracing.com/parts/c...SABEgJHbvD_BwE
The muffler design is similar to the original 86 muffler, you’d still have to fab the rest of the system. I almost ordered it up for mine but I need 3.5” or 4” as well.