We're going to let the box alone for a bit and turn attention to the Spanish cedar liner portion of the project. Just like cigars, wood needs to acclimate to its surroundings and in some cases, needs to age a bit to settle things down and stabilize. Spanish cedar is a good example of this process because of its variable sap content. The sap in this wood tends to settle in pockets and will leak out unpredictably. I've had this plank in the shop for over a year and I'm still waiting for it to get through with its piddling around. You can easily see where the sap has bled through to the surface. I'm pretty sure it has settled down and I could start slabbing it but I will give another couple of months of drying to make sure.