True different stokes:I did the opposite,i replaced both front floor pans and the pass side had just a little rust in the bends but I replaced the whole piece figureing the new metal floor pan was a little thinker and more solid so i cut the floor and replaced with the new material.the factory floors alsted near 40 years so the new ones should be in till the rest of the body is replaced or gone.Just seal the under side real good especially the weld as they will rust faster than metal.If you decide to overlap make sure you seal the overlapping area underneath with something like seam sealer so no moister can get in there.
