Would it be easier to split the MAP voltage input for Baro on the T-side and MAP from the E-side? Does the T-side pull the MAP value from the E-side ADC for the Baro, or does it use it's own ADC to do the baro update?

If it uses its own ADC for baro updates, it would be possible to lift the ADC pin, route it out to an unused pin, and just tie in a second 1-bar sensor and mount it in the airbox or something. That would also allow baro updates at any time.