I sprayed Rustolium liner from Walmart in my 69 and my 66 fast back conversion ,in the floor and the trunk on the 66 and i like the way it looks . I have seen spatter paint in the trunk also that looks nice .
The Rustolem looks great but I am really not set up for a large spray application. I am thinking of the Hurculon roll on application as mentioned by Cool Beans.
Rustolium - $80 a full gallon when mixed .It is a two part mix same as the others and just as tough but Cheaper . Takes over night to dry ,especially in cold weather, but just a tough as the expensive stuff and looks just as good