Your ecu can run N/A already.

Its not obvious how to do this and my implementation isnt ideal but it does work.

Select MAP sensor type as NOT FITTED.

Then rescale the IGNITION map BOOST scale to 0 to 10.0 psi
in divisions that suit your mapping requirements.

Then 0 to 10.0 psi represents 0 to 100% throttle position.
This will be echoed in the fuel map too.

Obviously then all map related settings become irrelivant.

Alternativly....

It is possible to use MAP on N/A but you will need to link all throttles
together with a pipe to the sesnor IF using throttle bodies.
You will also need to run a TPS too.