My secret? 3M brake cleaner. No lie. Comes in a spray can - get a few and you'll be done in no time. Enjoy
BTW - I did what you're doing a while back and have a post about it. Tried the 3M remover, Goo Be Gone, lots of elbow grease, etc. My uncle used to be a diesel mechanic and told me about a 3M rep telling him to use the brake cleaner on their adhesive to remove it. Worked great!