2001 Grand Marquis(or Crown Vic) Custom box

The 01 Marq has the same trunk design as the Crown Vic and im wanting to put 2 12 inch subs in the trunk. My issue is I dont want to take up a huge share of my main trunk area. Has anyone put a custom box above the gas tank where the spare tire usually sits? If so can you give me any advice for how you did it? Any information about how to do this would be really helpful! Thanks!

i have an 03 vic and i have 2 - 12" subs up there. it wasn't easy and it was built in place.That means cut the wood put it inthe car then put it together. it took me two times to get it right.

I built a box for 2/10s to fit this area in a crown vic. They were plenty loud for my taste.