I used that Goo Gone stuff you get at Home Depot. Soaked the stuff for hours and scraped it. It was a bitch! I think I got about half of it. This is after trying acetone, laquer thinner and mineral spirits. They didn't touch it.
I got about 90% of the thick stuff off the sanded the rest but that shit is still sticky so maybe I will let it sit for a few days and see if it gets hard and then use spray on adhesive over it and see if that will make the carpet stick good enough.
Also where can I buy a staple gun for those really small staples they use to secure everything?