After removing the carpet in my son's 67 chevelle we found that the floor was not quite as we expected. The right front floor pan has a area about 16" by 16" that has no holes but is real rusty and pretty soft. Any tips in replacing it? I have a new floor pan here and a mig welder and a plasma cutter,so I feel I have the tools. Should I just cut out enough to get to good solid metal or go further? the replacement floor pan is huge. Any help would be nice. Any other tips would be appreciated!! Thanks, Slime