The same chassis is used all the way through, from base model V6 to Z/28, so any wheel that fits one trim level will fit any another (except that brake caliper clearance may be an issue with some wheels, but the V6 gets the smallest brakes so nothing to worry about here
).
What is your goal here? You can install the RS/SS wheels which are 20x8 front, +35mm offset, 245/45 tires, and 20x9 rear, +40mm offset, 275/40 tires; or you could do factory 20x9's all around; or ZL1/1LE wheels and tires; or aftermarket wheels with the same or similar overall diameter and offsets. If you want to be conservative you could go with RS/SS sizes, or if you want width then ZL1/1LE sizes works; and 275/40/20 front, +23mm offset, and 315/35/20, +43mm offset (same offsets as factory ZL1/1LE wheels) are popular; a square setup with 10" wide wheels and +35mm offset is also popular and allows you to rotate all four tires.
The overall tire diameter ranges from ~27.85" to ~28.66".
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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