That reminds me when I was a kid my uncle went to change the tire on my mom's car and I was with him to watch. When he opened the trunk my Christmas gift was in it. Too bad he slammed it shut so fast I didn't have time to see what it was! It ended up being a cool tabletop pinball machine.
I've though about using under the rear seats. Only I go in my truck, but most people who don't own or look into details on the Maverick have no idea the seats lift up.
Last year, I wrapped a digital picture frame in a blanket, stuffed it inside an old camping backpack, and shoved it behind the spare tire in the bed compartment. No one thought to look there, and it stayed totally safe. The size fit perfectly too. I just had to make sure it was padded well so it wouldn’t rattle on drives.