Oh, I misread...I would not consider building up the crimped edge of a door panel with lead. It's too soft and there is not enough area for it to hold on.
I agree. I used lead in my resto, mostly over welded seams on patch panels and areas
at the edge of a panel, but not the edge itself. I learned how to lead as I went along, and it is a bit tricky, especially on vertical surfaces. There is a fine line between having the lead solid, liquid, or in the peanut butter stage necessary to work properly. The correct lead alloy is 30/70. Anything else has too narrow of a plastic temperature range and is virtually impossible to work with.
Also, do not sand lead. You don't want the dust flying around. You have to use body files, sometimes called vixen files. Another problem I ran into in the beginning is not getting enough lead down in the area you're working. You start filing and realize that there are some low spots. Well, you just can't add more lead as you will be melting all the lead underneath. So, basically you're starting the repair over again.
For a repair such as you want to do, welding is the best alternative.