1979 dogge transvan messing up

Hi everyone.  The first thing that brings me here is I/we have had a 1979 sportsman dodge "trans van" with a 360 engine for awhile now.  For a couple of years one would have to :goose " the gas to get it past the flat spot at much more than an idle, but It ran smooth otherwise and ran nice and cool.  I replaced the carb but it did not help. The van would stall out while going down the road and generally refuse to restart.  Sometimes it would restart after it sat for a few hours.  I dickered with the timing a bit, to no avail, however.  I might add that when a timing light was used, the lines or timing marks didn't even come up in the same universe let alone be apart. Not sure how long that was the case.  So I had to set it by ear.  The engine repotedly had less than 30K miles on a total rebuild, not sure thats factual....I mean I wasn't there to see it done.    Next, the van sat 5 years.    

Just this month, I charged the battery and started it, and same problem now except it has more of a tendency to want to overheat. And it idles slightly rough. And after a few mines, stalls out, more often than not not to restart for awhile.   It ticked for a couple of minutes but that smoothed out and stopped.    I replaced the coil and thermostat, fuel filter, all fuel lines, took off the gas tank and cleaned it well.  My fuel pump has pressure as is supposed to have.   I wonder if by chance the egr valve or the one way smog line check valves could be to blame?   Im really stumped.   Any insight you may have would be treasured.   John