A useful tool would be a spatula.
boards
"Floorboards" are tongue and grooved wooden planks that are used to make wooden floors.
yes
He tried to sneak quietly through the house, but the creaking floorboards gave him away.
A jack, hoist, or lift.
The prepositional phrase in this sentence is 'Beneath the floorboards'.
propaganda.
so you can always see
If you are talking about draining water out of the cab than they are under the carpet in the floorboards. There are a couple of them. Just lift up the carpet and you will see little black plugs. Just pull them out and your jeep will drain out.
There is a condition called cupping where the edges of the boards are higher than the center. It's usually caused by the boards absorbing moisture. If your floorboards are cupping, look for somewhere that moisture is getting under the floorboards. Possibly a leak.
A tool called a "Seam ripper".