Sanding/shapeing a mountain top

Need some advice.I replaced a lower(outer) door section on my Fard F100 PU.Where the weld seam is,everything slops away.Computer won't recognize my scanner or I'd post a pic.
If you go to the center(left to right center) and mark that point,,,the entire door slopes away from this point,,,going north/south and east/west.Otherwords it's like if you were standing on a mountain top,,,all four directions slope away(meaning,going down or sloping away from).This is a slow gradual slope that covers the entire length of the door from this point.
My problem is that I don't have a 'simple' valley to fill with body filler.I can't hammer/dolly it,so it is 'somewhat' up/down and I am sculpting!
I have made a center line with tape sanding up to and down to.I have used every gadget know to man as a sanding block and though I am about 2 primer coats(thickness) off,it still isn't acceptable for paint(gloss). Any suggestions would be appreciated.:(

Think of it as too much metal in the middle of the panel. It can't move sideways so it bulges out. You need to "shink" the area in the middle of the panel.

I can tell you that it can be done with a torch by heating small spots cherry red, then quenching with a wet rag. I am not a "metal guy" so I can't give you specifics. If you have a good metal worker in your area, you might consider taking the door to him for repairs.

i have had to shrink many body panels over the years more for my friend he like to over work stuff. it is some thing you may want to take to someone to do like said or you can cold shink it

Thanks Hotrodpaint and Pat.I am terrible at explaining things but it's not really the metal but the actual shape of the door.This is the lower door body line(actually)just above it in an area that is concave(concave from up/down,or north/south) on a 78 Ford F100.The door slopes down to this point and it also slopes down/away from this line/point going left/right or east/west when facing the door.If I didn't have it so close I would do what I should have done in the first place and bought an entire door skin.It's only paint thickness away from being straight(well actually,rounded).I primer it after every blocking and then wet it and I can see a slightly wavy body line.So I am shapeing(anew a concave area)that the entire door slopes away from.I have tried all kinds of pipes,hoses,in this concave area as sanding blocks but trying to get all the angles straight would have got me fired if working in a shop:CRY: **)

i think i now know where you are taking you want to gide coat it and run a long boad to get it ruff in and work a small hand sanding block at a angle cross your angle to the long bock lines this will work out the chop or if good you can hold a da at a 35 angle to the door and is will ruff and radi out an then paint sick it out