On my 99 i am in the process of cleaning my floors and cutting out bad rust and going to patch in a new floor pan. When all is said and done I am going to monstaline the floor. From the factory there is some kind of hard sealant stuff in the corners where the panels meet. You can scrape it off with a wirewheel and it just kind of powders / flakes off. What is this stuff and should I worry about removing it before i bedline? What is a comparable product to put back over my pan joints before i bedline it??

 

That would be seam sealer. You can paint/bedling over it, but the factory stuff is likely brittle and cracking at this point, if it is you should remove it and replace it, the paint may stick to the seam sealer, but if the seam sealer isn't well adhered to the metal it will flake/peel off anyhow.


You can buy automotive seam sealer in a calk tube at most auto parts stores, amazon, etc.
Dynatron 550 Auto Seam Sealer Grey Caulk - 12 oz.