I recently purchased a '74 Fabuglas Trident and will be restoring it. I have read many posts on this forum which state when replacing stringers, they should not come in direct contact with the hull, and should be spaced away with foam or other materials. I am not totally familiar with boat restoration, but believe I have the skills and abilities to undertake this project. My question is what type of material is used to space the stringers away from the hull and if I hang the stringers with supports about a quarter of an inch from the hull, is the aerosol insulating foam that is used to fill gaps for sealing something that can be used? It can be trimmed square to the stringers after curing, followed by fiberglassing them to the hull. If not, what products are available for this proceedure?