I need to replace the upper exit plate on my Z190 mast. I talked to Rigrite and US Spars. They have the part which is about $3 but the shipping cost to Michigan is about $13. This is nylon part. I would like to replace the exit plate with a stainless steel plate without doing any adjusting to the existing hole and will cover the complete opening. Has anyone done this? If so, please give me the part # and where to get it.Thanks for you helpLee