Hows the fuel pump?theres a difference between spraying fuel and spraying ENOUGH fuel,and, pumping the gas pedal on a TBI unit is useless theres no fuel bowl in that thing, is the map sensor hooked up?
are there any engine codes? If you don't have a scanner use a paper clip to read them jump A and B and turn the ign key to the on position and record the codes and post them on here. Also check the maf sensor too, either of those two will ruin your day.
4.3 V6 TBI GM......been there done that
Windows......biggest waste of time I ever did in my entire life