Here are some shots of my trunk floor and of the front floor pans (which are all in tact)...maybe you can use it for reference... I put a NOS OEM floor in my car... now all o fthe original OEM floors I have seen (maybe only 5!) must have been manufatured in late 71 or 72.... because the only difference on these floors, is the holes for the shock towers are on the angle, like you would see on a 72-74 cuda...and not on top like the 70-71... if you dont know what I'm talking about look at the close up shot below, and you will see, we drilled new hols on top, and welded up the old ones with the circle we cut out....otherwise it was the same floor...and fit like a glove...(you may have to do this on the new pnas??) on replacement pans, I have seen my friend weld them up, and hide the seem.... I'll ask him today a little bit about that... also down the line, you will need to use seam sealer to cover the seems...at first when my friend did it, it was too fine and neat of a bead...looked great, but I am going for originality...take pics of your old sealer for reference, if your a nutty fanatic like me...you'll see I re-did mine, to look like sloppy factory sealer...it came out awesome when it was painted... I will tell you how I did it later..
hope this helps??!!