trouble starting when cold

My 1996 truck with the 5.0 Vortec is having trouble starting when it's cold. I have to crank it over five or six times before it will start, although it sounds like it's trying to start by the third or fourth crank. This problem does not happen when it's warm. Fuel pump was replaced about two years ago, and I just replaced the fuel filter and changed the spark plugs. After replacing the spark plugs (they were actually shorter than they should have been -- amazed it actually ran) I have more horsepower, but it hasn't fixed the trouble-starting problem. Any ideas? I've searched the forums and it sounds like the problem is often the Fuel Pressure Regulator. Could that be the problem here? Thanks.

You need to use a fuel pressure gauge to see what the pressure is when you turn on the key.
It needs to go to 60 lbs. The pump only gets 2-3 seconds of time to do this.
If the fuel pump relay is failing, it won't get the voltage fo the prime. The oil pressure switch will get over 4 lbs when you crank it, then that will feed electric to the pump.
My truck got slow to start 8 months ago and it proved to be the pump.
There is a short pigtail (usually red) behind the fuse/relay box coming out of the harness. You jumper 12Vto it and the pump will run for further testing.
Bob B