No power to fuel pump

so ran fine for 2 days
id bet it didnt have only 1 gallon there.
or did you run it dry again.?
the pump is fuel lubricated and cooled
ran dry invites wrecking a good pump.

From remote site, it is hard to tell what is the root cause, and change pump was done in proper order -- you should post the problem before replacing fuel pump.
Here is what I will do, assume you can do a little by yourself.
Changing fuel filter should be easy by disconnect fuel hose (pipe) from the fuel filter . Since ASE mechanic did job in your house, I assume the old fuel filter is still in your hand. Change it back (replace new filter with your older one) to see if your car will work as before. This supposed to be done before replacing the fuel pump.
If older filter works, then you knew the new filter is the root cause. This could be resolved by replacing another new filter. If the problem appear again, leave the new filter in for over night to see if the new filter will work on the next day (you could use exiting new filter to avoid buying another filter, unless you will get a different brand one). If not, the choice is to use older one for a while when trying figure why new filter does not work.

If old filter does not wok either, then something is in forwarding fuel line between fuel filter and fuel ejection system. Then, that section needs to be cleaned. Assume the pressure is measured at connection between forwarding line and fuel filter.

if the fuel lines have any rubber fuel lines they could be sucking air. also try replacing the fuel caps, it may not be venting

Modern fuel injected vehicles will only run the pump for a couple of seconds to pressurize the fuel system at stat-up. The pump won't run after that until the engine is running or you are actively engaging the starter. The fuel pump and relay are doing exactly what they are supposed to do. Now, that doesn't mean the pump is building pressure like it should but the pump running for a second then shutting off after you first turn on the key is normal operation. You may have entered it, but I can see no information about what vehicle you are working on other than it is a truck. More information about the vehicle would help. In the mean time, I feel a compression check is an order and you should take a look at the oil to make sure there isn't any water mixed in. Some history would help as well, like if you have done any type of service in the last month, when the basic maintainence was done, how many miles are on it, etc.

I would suspect the fuel pump.The fuel pump is in the tank and I would just change it then set your timming back to the originale timming.

most likely a clogged fuel filter, all the impuritys laying in the tank got sucked in to the filter when you ran out of gas, and with air in the fuel pump it probably does not have the power to **** the fuel trough the clogged filter, replace the filter

make sure you have cleaned lines of all gunk

You say you replaced the fuel pump, what about the filter? If the filter is clogged it can cause this as can ignition. Since the car started for you after the fuel pump was changed the original problem was the fuel pump. But you should never change the pump without installing a new filter.

You could have a fuel pump getting weak or fuel pump relay. One other thing to look into is the oil press. switch malfunctioning or loose connection. The fuel pump/relay get's it's power through this on some GM vehicles. If you have a haynes manual look at it's wiring diagram to verify.

The fuel lubricates the fuel pump, so if you ran completly out you may have burned out the fuel pump. First you can do a fuel pressure test, it should be 41-47 psi, if low replace filter and check again. If still low verify pump is getting power then replace. Thanks