Shipping

I would make a wooden crate and secure the grille to the crate and wrap it in bubble wrap then put the top of the crate on and bolt the two halves together it will be pricey but its better than getting a busted grille or further more having to give a refund for a busted grille
I did just that with a Duster grill and bezels using USPS. The buyer got the grill cracked and tab broken. When he got it was packaged well, so they went out of their way to damage it. Filed a claim because it was insured, claim denied because the Post Office he took the damaged box too did not do any paper work! Filed an appeal yesterday, will have to wait and see.
NEVER USE USPS AGAIN!