Hopefully someone has some knowledge that can assist me. Any ideas are appreciated.

Truck won't start: It has been running rough for a few months and then would start and die.

Have done the following work:

New Ignition Coil
New Distributor (pertronix - no points / condenser)
Rebuilt Carb
Set timing to top dead center
Checked compression (holds at 120 equal all cylinders)
It has spark
Firing order is set to 1-3-4-2 based on stamp on head
new seals on valve cover
new seal on intake / exhaust
has good vacuum (*** hand when placed over throat of carb intake)
reversed distributor cap in case top dead center was off
spun distributor during cranking slowly in case top dead center was off
Tried to start with starter spray, choke open / closed, throttle open closed etc
cranks continually but no cough or catch