Here's what I've (tentatively) decided to do: this is going to be my 'rat-rod' truck...one that ain't purty by any means, it'll be loud and scary-lookin'.
I can't work on the '67 since I'm basically at the point where I need to start painting, but it's too cold to paint now, so I've decided that thrashing on the choptop will be my winter project. I was going to rebuild the 460 and drop it in this truck, but have decided instead to drop the complete 390 I have, that was originally destined for the '67. Since it's still together, I'm just going to steam-clean the hell out of it and drop it in. The goal is to have it roadworthy by springtime.The previous owner had replaced the floorpans, front cab mounts and rear cab corners and then sealed up all the joints with a tar sealer. While it might have been OK, especially considering the goal of this project, I decided that I did want to clean up and seal the interior and exterior floorpans with POR-15, which meant stripping it all down to bare metal....so getting the outside floorpans cleaned up was what was on today's agenda.
Here's a shot of the box removed and setting up on end, the front sheetmetal removed and the cab flipped onto it's back for cleaning.
After I got the bottom side about half cleaned up, I was taking a smoke break and walking around the truck when I noticed some bubbling under the primer on the driver's door. At this point I'm thinking "...oh hell, here we go again...", and I was right. After spending some time stripping the primer off the door, I discovered that the whole bottom half of the door skin was rusted and very beat up, and then just covered up with body filler almost 1/2" thick in places.
Since this door has been chopped, I can't just throw under rust-free door on (which is too bad, since I've got several)...I'm going to have to weld in a whole lower door skin. I decided to temporarily postpone the floorpans, and went ahead and dug out the cut-off tool and then cut off the skin.
I'm putting together a project update page with a whole bunch of pictures, it'll be posted tonight before I go to bed.
Oh well, I learned quite a bit on welding sheetmetal with the MIG when I was welding up my box seams, so I guess I'll find out if it stuck, when I have to weld in a lower door skin. 
