Thank you everyone for some fantastic solutions. I have been using the scrap bits of wood to secure the plank but have been using pins instead of nails. Not sure if the nails I have will allow a scrap of would underneath the nail head but will give it a go. I see some people  are using cocktail sicks as tree nails and I have a number of these at had so might give this a try and see how that goes. I could of coarse as you suggested just use the nails and file the heads flush with the plank w