Truck starts, runs, but it has a terrible time remaining running and when I give it some gas it seems bog down but then finally comes to life. Too nervous to take it on the road until i figure it out. Sometimes it seems like it is about to find an even idle, but then it will start to drop RPMS under 1000 and just sort of sputter a bit. Around 2200 RPMS she runs and purrs like a kitten. Thoughts?

Quick update - I do hear some hissing near the upper intake - can't seem to isolate exactly where it is coming from but I'm guessing a serious vacuum leak?

 

Yes, reads like a vacuum leak

Couple of things you can do

Smoke test
Get a Cigar, thicker smoke
Take off the Brake Power booster hose, from the booster
Blow smoke into it
Look for smoke coming out

Cold engine Ether test
Get a can of Quick Start(ether in a spray can)
Disconnect Fan belt so no Fan, also no water pump or alternator
Start engine
Spray ether around intake, engine should "ping" or react when ether is sucked in
Try to localize where the leak is

YOU CAN ONLY RUN THE ENGINE for 1 minute maybe 2 without the water pump, so be quick about it, it will also be very quiet in engine bay with no fan so you may be able to hear the leak easier