My townhome was built in '68, which I am in the process of remodeling. I would like to replace the tub/shower with a new tub/shower. I plan to put in a new tub and tile. When I measure my bathtub I get the dimensions 58.5x28.5 which are very odd dimensions, is it possible that there are 3 inches or so of tub hiding behind the tile? Is there any way to know for sure without damaging the tile? Any suggestions would be helpful, any tips will be appreciated. Thanks!