Hi James.
Great job on the truck so far..I see the line that goes from the dash to the engine compartment is still intact..It is the line with the protective coil casing around it that runs between the floor pedals ...(It could be your speedometer cable also)
If that is your temperature guage sensor line that runs from the temperature guage to your engine block..(I see that the engine is missing but look for that sensor line..They may have taken it out of the block in one piece..)It is a mercury filled sensor bulb and if you are lucky it will be in one piece...with the bulb still intact...DO NOT CUT THIS LINE to remove it..or else ,not withstanding environmentally bad mercury things,that will be the end of the temperature guage...and don't heat it with a torch...that too will destroy it...
There is a section in the manuals on the care and feeding of this beast..
Looks good so far..
I see the butt plate holders for the rifles on the floor of the truck and the floor looks in great shape..
Great work..