...some pretty decent instructions on how to apply it. I've always just followed the directions and had excellent results. You are correct, they say not to scrape/sand off all the rust...POR-15 needs something to 'grab' onto. You will want to put some top coat over POR-15 after it's dried because it eventually turns purple when exposed to sunlight for long periods of time. Again, this is all stuff covered in the instructions.
Another thing you might wanna' consider is leaving off the rubber strips indefinitely.
Good luck,
Tim G.
'91 535iM w/ no door strips
Originally Posted by Derek A.