Resonators are more for reducing/eliminating higher frequencies (rasp) and don't do much to reduce volume. A big (oval) muffler on either side is probably what you need. Smaller (cylindrical) mufflers may not be enough to make a big enough difference.
You could also try replacing the X-pipe (or H-pipe) with a muffler/X-pipe combo (for example, part number 11386 by Magnaflow,
https://www.magnaflow.com/products/1...-muffler-11386), so you'd have just one oval muffler, although I did this on my V6 which also had cats (no other mufflers/resonators) and it was decently loud so in your case it may still be louder than you want.
__________________
Overkill/Self Tuned; Mace Camshafts; K&N Typhoon Cold Air Intake; Ported 80mm Throttle Body/Intake Manifolds/Manifold Spacer; Solo Performance High-Flow Cats, Cat-back Exhaust; Vitesse Motorsports Throttle Controller; Elite Engineering E2 Catch Can; BC Racing BR Coilovers; JPSS Delrin Radius Rod Bushing Inserts, Sway Bars; Pegasus Aluminum Rear Cradle Bushings, Camber/Caster Plates; Z/28 Toe Links, Trailing Arms, Upper Control Arm Bushings, Rear Shock Mounts