This is why butt welding gets tricky. Unless things are lined up perfect you can find yourself patching in gaps . I would recommend Cleco’s - you’ll wonder how you did without them. 

I learned my lesson with these panels - only cut off what’s bad on the original panels. Removing all of the old panel all the way to the inner rocker panel is usually not necessary , usually not much rust all the way up there anyway. I didn’t hardly catch this issue when I did mine. It made the floor slightly off level 

1 hour ago, Zaspen said:

Bottom of rocker side of the pan is part way up the original weld surface but yet the pan has to bend up to get to the rail.  Is this normal?

Try and think of the pans as only 90% correct, you have to make the pan fit your car,  if you think you don't need that extra 3/8" on the rocker side of the pan and you still have enough work with, cut it off.  Measure twice cut once?  Did you keep the original floor pan, you can solve a lot of problems by having a look at the old stuff if you still have it.

I like the 90% thought! I guess I just need to be creative and not expect perfection.  Thanks for all the replies.

Cleco’s are a great way to get things lined up before cutting thru for the butt weld. The zip disc leaves a nice 1/16” gap to weld into.





On the passenger side I only used 3/4 of the floor pan and kept the tunnel curve section as it was good.

Is the general thought to get the pans in then fab and install the firewall patch panels or the other way around?

 

Pans first, firewall patch second, that allows you to match it perfectly and make it original.

When you’re done it looks like new!

I hope mine looks that good! 

6 hours ago, Zaspen said:

I hope mine looks that good! 

He illustrated the technique well. Copy what he did. Take you time. Get some dollies and hammers, cheap ones will work. With a good welder you'll be fine. ?

8 hours ago, Zaspen said:

I hope mine looks that good! 

Wait to you see that same photo with all the gas lines installed, very sharp. Mark, that's your cue?

As requested...

 

Bottom porn.