Each fender had a few minor dings and dents, so I spent some time tapping them out as much as possible, before finishing them off with a thin layer or two of filler. Here's a shot of the fenders after applying the filler but before the sanding:
Most of the areas you see with filler are dings which are too small to even see with the eye...but you can just barely feel them. However, since the truck will mostly likely be painted black, they needed to be addressed, since they'd be much more obvious after painting if left alone. I'd estimate that 98%-99% of the filler in each of these spots was removed during sanding. The first trip through the sanding process was a learning experience. I tried using a hard rubber sanding block at first but found that it was still too flexible and it tended to try to conform to the dent and I sanded off TOO much, so I ended up going back over some of these with another thin layer of filler.
In between applications (while it was drying) I was getting started stripping down the rest of the '68 parts truck. When I first put the truck in the shop several weeks ago I tried removing one of the top header bolts, and could see the head of the bolt start to turn but the other end wasn't.
It's been in the shop for a couple weeks now, and I've been religiously spraying the header bolts with PB Blaster and letting it do it's job, so I wouldn't break any off during removal. Today I tried removing them...with great results. Most came right out with a wrench. (That PB Blaster comes through again....man, that's some good stuff!) I got them all out except one, but only because I couldn't get to it! I'm going to have to just leave that header on when I remove the engine and then try to remove that last bolt. Anyway, I got sidetracked with the parts truck and didn't get around to sanding off the final layer of filler on the fenders, so that'll have to wait until next time. But I only have maybe another 30 minutes worth of sanding before they're ready for paint.
Not sure when I'll get another shop day, because my wife has to work all next weekend. However, depending on things at work, I might take Friday off....and get started on the doors.
I'll get another project update page posted within the next day or two...I'm too tired right now to mess with it.
I'll be calling you to set an appointment for you to strip my 68 cab 
