Signs of a bad fuel pump?

Edit: let me start by saying my fuel line had a leak and I lost every bit of fuel in my lines and tank which was not a lot, maybe 1/8 of a tank.

Still wrestling the 84, got the timing set, dumped fuel down the throat and got her to show me minor signs of life but she won't fully light off or stay running.  I pulled the main fuel hose into the carb and found it bone dry.  Half a tank of gas in the truck, so that's good.  I separated the fuel line and tried to crank to see if any would come out and nothing.  I loosened the output fitting (did not fully remove) of the pump on the side of the motor and when cranking it is barely dripping.  I know these are low pressure systems but would this be a sure bet on a bad mechanical pump?  And are these rebuildable or just a replacement part?

They aren't rebuildable, so replace it.  But first, I've had situations where a truck that hadn't been started in a long while wouldn't pull gas into the pump.  So I put a little bit of air pressure into the tank's filler and that pushed gas into the pump.  Somehow priming the pump worked.

If its a "ripped" bladder in the fuel pump, your oil is contaminated with gas....

Do these pumps dual purpose as fuel and oil or is just in the way it mounts up?

It is the way it mounts.  There is a diaphragm that pumps and if it splits then gas goes past it into the oil.