so here is what my trunk area looks like,

 

Cancer. Butt Cancer.

 

Dang! I had a xj like that. I ended up using it for parts.
You could fix it if you got the know how. But thats allot of work.

What you plan on doing with it?

 

i have to keep it for now,
i plan on welding 1/8inch steel plate to every thing but what
welding method should i use and should it be on the frame that i weld on to or the existing sides.

for the frame i wanna do 1/4 inch deep U stamped steel

 

I just finished my floors I used 16g cold rolled. I welded it all the way around and drilled holes through the sheet metal right over the sides of the frame rail and welded the holes to the frame.

 

how much is that stuff?

 

I feel your pain, man. Mine looked like that 2 weeks ago. What I did was remove the fuel tank, and went nuts cutting out all the bad metal with a cutoff wheel, then wire brush the inside of the framerails , apply rust penetrant, prime and paint the inside of the rails. Then, I used appliance sheet metal and riveted it to the frame and wheel wells to make a new floor.Last, sealed it up good with rustoleum, great stuff foam ,and about 50 bazillion coats of undercoating. Also cleaned the rust off the fuel tank and undercoated that too. My hands are still torn up from it, but it was worth it.