Hard cold starting

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Need some help here...

I have a '96 S10 4x4 with the 4.3L. Over the past year, it has slowly become harder to start in the morning. It now takes 6-8 twists of the key when it's cold. After it's warmed up, it starts up first crank, no problem. I have changed the cap, rotor, fuel filter. Spark plug wires are fairly new MSD. No change.

I'm thinking it might be the fuel pump and/or FPR. I picked up a fuel pressure gauge and hooked it up to the valve at the back of the engine. Here's what I got:

COLD
Turn key, pump primes and in about 3 seconds reaches 53-54 PSI.
It bleeds down to about 11 PSI after about 15 minutes.
Running at cold idle, I have about 51-52 PSI.
If you shut it off before it's warmed up and try to start it again, the pressure primes to only about 51PSI and it takes about 10 key-twists to start.

WARMED UP
Turn key, pump primes to 54 PSI. Bleeds down to about 30PSI after about 1/2 hour. Starts right up. Running pressure is about 51-52 PSI.

The return line appears to be steel all the way back to the tank, so I can't crimp it to test the bleed down.

Does this sound more like the pump going bad or the regulator ?