34 ford floorboard replacement

Hi guys need more advice just received new bitchin front floor boards sheet metal for a 34 fordor. already installed new firewall rececessed for small block chevy.
Ok the question is actually a couple the floor board know is stock no rust tho no toe panel do I just fabricate to old floor. what i am asking is fill battery hole off new panel and use new panels for toe panel to firewall. Of course use new panels for transmistion cover. been looking all day did not find any answer to my question so before I start this wanted to ask you guys. Any way if I do replace all front floor board do I but weld or over lap old floor and either way do you weld solid seam on panels? Or every four inchs and stich and seal? Also body is on frame do you weld above or below is there need for bracing before cuting old floor out sorry no pictures yet can post later.
Just second guessing myself think might be eaiser to patch batery hole and toe than weld tunnel on top what do you guys think. thank you in advance for any coments sure helped me when I installed firewall just don't want to mess up.

Hi Mark,

I gave you this link when you were installing the firewall. They address floorboard installation on it, too. Hope this helps....

http://directsheetmetal.com/pages/typeinstall.html