Sounds like good advice. Now you got me thinking.That fuel pressure regulator doesn't look like what's in the K5+ pump modules....at least not what my K7 looked like. Were I you ....I'd just get the cheaper one I linked to earlier and call it good. The fuel pressure regulators don't really wear out...as Missing Link can attest...so just replacing the actual pump and bypassing the stock filter all that's needed.
One thing if you're in there to the pump....you'll see the regulator is behind a plastic cap with a triangular opening for the fuel it dumps to shoot back into the tank. While you're there I'd recommend drilling a hole in the center of that retaining cap to allow the reg to vent easier. Mine...with a high performance pump (mistake) couldn't dump enough fuel to regulate the pressure and it was doing crazy pressure fluctuations as the injectors fired especially at low speeds. Killed two fuel pressure gauges even with a damper installed in the line. When I vented the cap the pressure stayed much more steady and believe it or not the engine ran smoother! Not a placebo effect....the back cylinder gets shorted for fuel with the normal setup at low speeds.
Front cylinder takes a shot...this lowers the rail pressure but the reg takes a little bit to react...then the rear cylinder takes its' shot of fuel....now the rail is seriously low on pressure and the reg is just beginning to react and close to raise it back up again...which it does then overshoots a bit just as the front cylinder is ready for fuel again. The cycle repeats with the pressure fluctuating over 20 psi and this is partially why each cylinder has its' own mapping in the ECU. To smooth things out...it's so much easier to just run one map for both and make the fuel pressure stay more even on both jugs. The inexpensive Caltric pump will do what you want without worry....why spend more for possible pressure problems down the road?