Drivers side, 10 - 12 inches from torque box/rocker side back has a gap about 1/4 wide and can't pull it tight. I could weld as is but I feel like I want to put in a fuller strip to close it. 1/8 maybe.

Thoughts, leave it or add filler?

 

any pics of the situation what are you using for floor pans? remans? i would make a filler strip but a pic would be best. does the door line up nicely even with the gap?

 

I would like to see a pic if you can.

 

Second one will show lines on the bottom of the pan and the top of the flange and that gap is about 1/2"
The car is all done and new torque box. There is no removing the pan at this point and the gap will need to be fixed by some other way, it's a finished car.

I was thinking about cutting the pan and filling the gap using a copper backer or since I am putting sound deadener, I could put a patch on the top and fill under.

What is best?

 

Well, I still cant tell "where" on the car I am looking at? Is that the rear torque box in the pic and is that where the floor meets the rocker at the rear passenger side?

If so it looks like it is touching and then the gap gets wider.
You could just make a slice in the pan about an inch over, from that point to the end of the pan where it meets the box, use a wide dull chisel and smack the edge of that fold so it meets up with the inner rocker (and goes back to a nice 90º) and then make a small pie shaped piece to weld in place.
That metal is thicker than much of the rest of the car, and its new so it should be able to blend in perfectly.

 

Made the picture smaller. Is front torque box you are looking at.

 

welding rod. Looks like you're in a seam. Lay the rod in place and tack both sides, until you have a single weld and then grind it down. I discovered this old school technique for door and panel gaps, and it looks like it will work here too. Just a thought.