Truck wants to die when I put in gear
 

I have 90 Ford F350 with the 5.8L 351W..Originally started out with a no spark problem..Truck was running fine b4 that..So started ruling out stuff..Replaced the plugs, wires, coil, ign. module, then when I replaced the distributor I got it to run again, but it ran with a really bad hiccup or surge while driving...Wasn't sure what it was..Checked fuel pressure thru schrader valve and it's got plenty of pressure, changed the fuel filter, changed MAP sensor, and changed Throttle position sensor..Still didn't help..So then I thought maybe a defective Ignition Module, so i replaced it, still the same, then I exchanged distributor thinking it was defective...Now the truck seems to run better, but only when in park it runs fine, but as soon as I put in gear it seems to shift into gear hard then want to die, can't even get it out of the driveway...Please HELP!!!:confused:

have you checked you vacuum hoses.