It's just a hobby. A money and time sucking hobby.
As for the box, I used fleece from Walmart. I normally like to use unbacked auto carpet but because of I need some stretch to get into the pockets I used the fleece.
After the resin was put on I used Long&Strong in all the corners and places I couldn't lay mat. I then put on about 5-6 layers of mat on the inside. I used Rage Gold on the outside to fill everything in. Then came Featherfil. If I use to do it again I would shoot the entire thing with SlickSand instead and then Rage the low spots. I think it would save a lot of time.