boost limit fuel pump cutout

[ckrug7380 at comcast.net]

I have an '89 200TQ (my second), and I've been contemplating cranking up the boost a little.  I remember researching this before, and there's a modification to the ECU to disable to fuel pump cutoff at 1.4 bar.   But, I had an idea.  Since the ECU gets it's boost information from a dedicated boost hose, wouldn't it be possible to cut that line, and install the following two items in parallel in that line?   First, a pressure regulator set at just below 1.4 bar. This would ensure that when the boost goes above there, the ECU only sees a "normal" reading.  The second item would be one of those nifty little boost valves that Rick Gillis makes (www.boostvalve.com).  Set it to what you want your maximum boost to be, for example, 1.7.  If something should go wrong and the boost exceeds 1.7, the boost valve would open, bypassing the regulator, sending full boost to the ECU, killing the fuel pump ground.  I think it will work, unless I'm missing something.  
With this system, the ECU should retain a correct boost signal except under WOT, and you still have the failsafe of the fuel pump kill.   Anyone have an upgrade wastegate spring they don't need anymore?  Oh, that reminds me, on that wastegate actuation... does the boost pressure sent to the actuator pull the gate open, against spring pressure, or assist the spring in keeping it closed?  It makes a difference in how I proceed.  Thanks

Calvin K.
Indy