Hostetler Decathlon
Hi Joe; I did not add any ply to the top of cowl area as the screws are only for scale looks and are not needed for strength. I used longer than necessary as they are easier to work with than the very short ones. The longer ones do go thru into the wood and may add some strength. You could always put the screws in and remove them, thin super glue the threads but I think this is unnecessary and not needed. The screws and microballon comming is really for looks only cheers John