ifly 747 engine versions

Can anybody let me know or help me convert the Ifly 747 to different engine models than just the GE version? Specifically, I want to use the POSKY repaints and models, and since they come with excellent flight models, for all different versions of the 747, it would be nice to fly them all with the Ifly avionics.1. Can I use the POSKY .air files? Are there specific things in the Ifly .air file that are tied to the avionics or FMC, and if there are, how would I go about adapting the POSKY air file to fit the Ifly avionics?2. How would I change the Ifly FMC to recognize different the fuel flow rates and thrust values? To me, this seems to be the hardest part.any help would be much appreciated.thanks