Mark,

This information if the the 1954 Truck Shop Manual, page 6-18 . .

Plug gap: .035 (20-25 lbs torque with new "gasket")
Point gap: .016" (.019" new points)

Set idling speed to 450-500 rpm
Set mixture screw to highest vacuum reading (should be between 17-21 inches)
Reset idle screw, if necessary

Ignition timing (cam angle/dwell 38-45 degrees with .016 point gap):
- set octane selector to zero (middle mark)
- timing light connected t0 #1 plug lead
- run at idle (no instructions to disconnect the vacuum line)
- loosen clamp screw on distributor (on the vacuum advance, behind the distributor).
- rotate distributor until steel ball on flywheel lines up with the pointer on the flywheel housing.
- tighten clamp screw on distributor.

If idle speed changes significantly, redo carb speed/mixture and then redo timing.

Make sure manifold heat (riser) valve is moving freely (and has a god spring)

Tim