Need some help

[EVILDOR]

This is my .first post but have been a member for a few months. To start off with this is a great site. I have a 72 c20 and a 87 k5. I need help with the 72. It has a 350 an the issue is driving the other day stopped at stop light idled fine for 5 -10 sec then wanted to die, put into neutral an let set at 1500 rpm light turned green put in gear an took off, happened once more at next light. drove another 10 miles parked an it sat for few hours drove 15 miles home no problems. truck sat for 4 days, drove this am to breakfast 4 miles away ate than on way out it died. after cranking on it for few min got to start but ran rough an if took foot off gas would die. limped it home let sit few hours went out pumped gas twice an fired up ran normal for 10 sec than wanted to die, was giving it gas but would feel as if starving for fuel. thinking fuel pump, anything else I should be thinking. Checked all lines , fuel in tank all is good thanks for any imput