i have to make a repair to our floor as it has a crack going across the floor , looks like a fault in ply ,i have been told to scew and glue a new piece of ply under the van over the damaged part of floor.my question is how thick is the floor ply in the van, we have a 2012 model 16.49-1 jayco expanda onroad, so i can work out what size screws to use that wont penetrate the floor into the interior of van as in the middle of floor between fridge and wardrobe . thankyou in advance.