Thanks again all, I wish I had something new to report on this effort but I needed to use the truck so I just put everything back together for now and got it back on the road. I am aware that you need to have the axle out and I did have it removed when I'd tried adjusting the shoes. I also tried pushing the bolts into the springs to adjust things but didn't seem to get them to budge. I didn't try pulling on the bolts though so may give that a whirl the next time I feel ambitious.
I was able to get the drum to pull away slightly from the backing plate and tried to slip a brake spoon and a small prying tool in there. Unfortunately, I couldn't seem to get things moved far enough to manually push the shoes back. The lip on these drums really does a good job keeping one from getting in there that way.
Thanks again for all the advice and I'm sure I'll be consulting again the next time I know the truck will have some down time. I don't know how I ever got along without a big truck like this before?
John
1935 Chevrolet 1.5-ton 1963 Oldsmobile Dynamic 88 2-door
1965 **** F-250
1980 "Honda-Davidson" CB-750 Custom
1989 BMW 325i Convertible (wife's car)