DC-16, please make throttle stick units universal

Please complete the non-centering throttle stick units with that few mechanics parts needed to support both non-centering and self-centering mode for omitting that omnious mode 5!
That would help both dealers who would need only two instead of three options in stock and it would help also customers, as mode 5 transmitters are almost unsellable if one decides to go for another transmitter at some time.

And please offer the mechanical parts needed for changing an actual non-centering stick unit to self-centerring as an upgrade package to existing customers.

Regards, Gerd