Man does this bring back a bad memory, my ole lady drove my 95 suburban down to her folks house in Belzoni Ms, just a few weeks ago.
My surburban only had 244,000 on it so i have no idea why it messed up..lol
But it's wents craps on her down there and she had no other option but to take to the country boy shop down there. Sounded like it was doing about the same as yours, hestating and stuff so here's the low down.
It ended up being the fuel pressure regulator, but that was after they put $500 worth of other parts on there first, here's a short list:
fuel filter, fuel pump, new coil, new high tension lead, new module and stator and of course the whole regulator assembly not the 40 dollar kit.
They said they clamped off the return fuel line and it ran great so try that, just might be your regulator.
Goodluck, Cp