27 PSI is normal fuel pressure for an injected engine. If it was truly coming out of the fuel pump overflow, most likely you have a bad fuel pump diaphragm and need to replace the pump.
Turn the boost pump on and see if you can duplicate it.
You can also get fuel out of the FAB if you turn the pump on with mixture in the rich position, as you will flood the cylinders and it will run back down the intake tubes.
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