How to set a throttle value from button press when using FSUIPC calibration

[Fabo.sk]

Hi,

if my understanding is correct, the functionality for buttons to "Select for FS Control" options "ThrottleN Set" with parameter does not work when "Direct to FSUIPC calibration" is used on an axis.

I would like to use buttons to control reverse range, while keeping the axis with no reverse.
Is it possible to send a value to throttle axis somehow? using Input Event or something? to enable this?