This website is probably pretty useless to you. You need to find one of those much more usefull websites that is dedicated to wheel offset, camber, fender rolling, and fitting tires with a six inch treadwidth on a ten inch wide wheel. Generally this site focuses on modifications engineered performance, driveability, and reliability. You should find one dedicated to more useful data.
Now that that is out of the way, my 15x10 -0 fit fine up front with 1 inch spacers effectively making them -25. The problem was the big 23x11.5x15 hoosiers. I would bet that a slightly more narrow tire (or better less offset) would have done the trick.