Is it leaking oil or burning it? The valve stem seals might be dead (the #1 cause of oil consumption). Get a rocker cover gasket that is made from high temp silicon. Try 'Stone' gasket kits. Rumoured to be repackaged OEM parts. They are a mix of Ishino gaskets which is a company car manufacturers use as a supplier. Current prices on ebay are pretty good - https://www.ebay.com/itm/Mazda-B2600...dVtMgc&vxp=mtr