How to Create Flyable AI Aircraft

Back in the FSX and P3D days, it was relatively simple to add a cockpit/panel to an ai aircraft and have some fun flying it. I’ve been trying to do so tonight but to no avail with the AIG aircraft. I believe I am performing all the steps correctly but cannot seem to get the aircraft to show up in the hanger.

Has anybody successfully attempted this feat? If so, how?

I‘ve tried as well with the SAIB A220 but with no luck, would appreciate if anybody could help here since there are some aircraft missing, that I would love to fly.