Inside Bed and Bedrails bodywork question

Edited: 6/27/2005 10:41:55 PM by SlammedAcroRam

I had some metal work done inside my bed and worke into the bedrails. I want to smooth it out so I can paint it but I'm pretty new to body work. I am attaching some pictures below. Do I need to weld the bed out entirely to do the work or can I leave it spot welded. I'll probably spray bedliner in the inside of the bed and paint the rails back black. How different is it if I decide to paint the inside too. Any products or methods of laying down the body filler and sanding it out are appreciated.