I wasn't going to post this until after the project was complete and the results were in but now that its done I'm happy to report that it was a success. Measure the inside dimensions of the cooler then cut Styrofoam to fit the inside walls, I used (1/2" and e6000 glue that I found at Lowes) and after I was able to keep ice for well over 30 hours and only lost 1" inside volume and was able to keep 8 of the larger size gator aide bottles ice cold even into the next day. the hardest part was cleaning up the crumbs of Styrofoam.