I'm installing a Brazilian Mohagany (?) entry door in a concrete block entry. The frame or jamb (?) is also wood, unsealed. I know it must be sealed. I've got a jar of DIY bedliner I used for coating a trailer. Would that be good, ideal, bad? If not what would you suggest? Door was $1,300, weighs 160# and is beautiful. Don't want to screw this up. Thanks.