Do I need fasteners to mount these fenders, or are they included?

Fasteners are not included with this set. You'll source bolts, washers, and clips based on your OEM attachment points. Have your service manual on hand to confirm the correct fastener type and placement for your setup.

What prep work is needed before I paint these?

Sand the entire surface with appropriate grit to promote paint adhesion and remove any gloss from the Raw FRP finish. Wipe down with a tack cloth, then apply your primer and topcoat system of choice. Clean masking and proper surface prep directly impact final paint quality.

Will these fit my base model, or are they ZR1-exclusive?

These are engineered for Z06, Grand Sport, and ZR1 models. Base model owners can install them, but the body-line geometry requires modification work for gap alignment and proper fitment. Evaluate your bodywork and drilling points before committing to the install.