Dinitrol ML: Required amount for cavity sealing?

Dear experts, my Datsun 280 ZX from California has to be flooded, because otherwise it does not survive the weather in D. My idea: Doing yourself with Dinitrol ML as a spray can and a cavity probe about 60 cm long, 4 mm diameter. How many cans (500 ml) do I need? At what places do I have to open or drill? Does anyone have a plan for Dinitrol or other manufacturers? Who has collected his own experience in this procedure and can tell me some tips? Alternatively: Who could sowa What costs do I have to reckon with? still what: Beginner’s question: When protecting the underfloor, leave out the silencer 1.) Exhaust paint on the same and after that 2.) Underfloor treatment (Owatrol oil, Brantho Korrux 3 in 1, Dinitrol ) or only 2.) and then apply the omitted 1.)? The exhaust paint can drop 600 degrees Celsius. Thanks for every tip! Pit