This Thread has some info also.I scanned the indexes.
You can view them
HERE Not sure if Photobucket is viewable.
From those scanned indexes you can find the Section & Sheet number for the particular part of the truck you're looking for.
Mainly 3100 or 1/2 ton indexes
01> Sec.. 0 sheet 1.00... Model 3100 Chassis instruction index
02> Sec.. 0 sheet 1.00... Model 3000 Cab & Sheet Metal instruction index
03> Sec.. 0 sheet 1.00... Model 3000 4000 6000 Electrical & Instrument instruction index
04> Sec.. 0 sheet 4.01... Model All Cabs LD RPO 264 Unison Seat instruction index
05> Sec.. 0 sheet 13.00. Model 3000 RPO 314 Automatic Trans. instruction index
06> Sec.. 1 sheet 1.00... Model 3000 4000 6000 Cab Welding instruction index
07> Sec.. 1 sheet 2.00... Model All Cabs Seat Frame instruction index
08> Sec.. 1 sheet 3.00... Model 3100 Under Body & Dash & Toe Panel instruction index
09> Sec.. 2 sheet 1.00... Model 3100 Frame Assembly instruction index
10> Sec.. 6 sheet 1.00... Model All Engine instruction index
11> Sec.11 sheet 1.00... Model 3000 Chassis Sheet Metal instruction index
12> Sec.14 sheet 1.00... Model 3000 Cab & Sheet Metal Sealing instruction index