The fuel pressure too high? you have the jeep pump, in tank, for the multi point injection ...right.
I agree the FPR should only keep the pressure at the required 12-13 lbs for the tbi, regardless of the pumps capabilitys. Maybe the return line is blockked or pinched? that would shoot the fuel pressure up a lot.
If an injector was leaking on a TBI you would have 4 cylinders getting to much fuel
Have you checked the Fuel Pressure?
have you looked at ALL the plugs?
Fact is stranger than Fiction