Did some digging and found some good information that I am going to try. Maybe it will help others dealing with the same issue.
"Kinda old....82. A lot of time on stuff.
I have worked on these for years, and have a very specific question. Is this problem only the first start of the day, and possibly worse after a weekend, or multiple days?
If so, here is your problem.
On the filter base bolted to the firewall, there is an "O"ring that is the problem. Lets air in when the engine is off, and the fuel drains back into the tank.
The engine will start on the fuel trapped in the injector pump, and then in about 6 seconds, the air will hit, and require a bunch of cranking to get that air pumped back out. Sound like the problem?
Remove the filter, and the base.
On the back side of the base, there is what looks like a large star washer, but is a retainer clip, about an inch and a quarter in diameter.
Pry that retainer out, and remove the gizmo it is holding in.
There is a skinny, probably red, "O"ring on that gizmo, and I'd bet a doughnut, that "O"ring will be all cracked.
That gizmo looks like a pressure sensor, but I have never seen one of them connected.
You can try to find a new "O"ring, and put the thing back in, but in the 6 or 7 trucks I have had in my fleet, where that wasn't even connected, I replaced the first base...kinda pricey...but since it wasn't connected,I just cleaned the opening in the base real well on the rest of them, and filled it with J.B.Weld. Never had a problem with it since.
As for a check valve...the way the block mounted transfer pump works is two check valves, and a diaphragm.
Over a period of time, the fuel will seep past those check valves.
A brand new pump might make it seem better for a while, but the "O"ring is what fixed mine."
Will do the qiuck fix and cover the hole in behind the fuel pressure switch with JB weld and be done with it!!!!!