Removing glued down floor insulation?

[HUSSEY]

Ok...been working on cleaning out my cab down to bare metal. After about three hours effort, I think I've blown out all the mice nests and poop from all the nooks and crannies.

Next I want to flush the interrior out with water and cleaner but before that I want to get that insulation stuff glued to the floor and firewall out of there. When I peel it up half comes off and half sticks.

Any pointers here? I was going to tackle it with a gasket scraper and some degreaser but wanted to know if anyone else has come up with a good method to get this stuff gone quick and easy.