Old floor pans out and will be fitting and drilling new AMD full front pan and rear footwell pans in the morning.

Do I need to remove edp from around holes for plug welds (edges of panel and Crossmembers)?

How about the rear footwell pieces where the new panel slips under the rear seat sheet metal?

Thanks!

I do. I then use weldable primer in the bare areas. It comes in a spray and brush-able container.

As a standard practice you should remove the edp coating. It will burn off from the heat of the weld. Replace with weld through primer. I strip all edp on every panel. I have found on the metal when doing so.

The point of removing the EDP is to get a good contact to strike your weld. So really, you only need to remove a small spot at each weld point to achieve that. However, the edp does burn off around the weld area, exposing bare metal which will oxidize very rapidly. "Apparently" weld-through primers tend to melt rather than burn off, basically sealing the weld in the pinch area. True or false ... maybe someone else can shed some light on this. I've seen a lot of photos of guys who just remove a small patch for each weld. I know for a fact the edp will burn off further than they've removed. Maybe the thinking is the seam sealer will seal out moisture but by the time they apply it it will likely be too late, oxidation will already have started.

Right now I have more faith in the weld through primers. I clean edp off the whole strip where I'm going to plug weld (both pieces) and spray both with weld through primer.

With mig welding, you need the shielding gas so weld is clean and not porous. If burning off edp coating, the smoke affects weld quality also.

any paint , coating or even rust is a contaminate to the welding process. do you absolutely need to remove it . no . you can slightly over heat a weld and help clean it up some. it does affect the weld quality to some degree. if you clean the spots where you plan to weld , that's all you need to do . all areas that are burned are going to be sanded before priming/painting is done anyway.....