Thanks man is there a specific brand or type? When I Google it I get these kind of big ones, would I just attach to the end or open it and do surgery? 🙏 10PCS 100mm 2.4G Receiver Antenna for Frsky X4R X4RSB XM XM+ R-XSR Replacement Antenna IPEX 4 V4 Port S6R S8R F30 F3OP F40 F4OP https://www.amazon.com/dp/B07JFZDYVS/ref=cm_sw_r_awdo_1W5QFCX99PY92MNMSZ72
OSD is just the display. Some "OSD" systems have flight controllers that come with, you need accelerometer info and other data to put it up on the screen, it's the flight controller that does the work and interprets that data, the OSD just overlays it on the video image to your goggles.
http://www.ebay.com/itm/like/391209749907?ul_noapp=true&chn=ps&lpid=82
Being a pilot yourself, you may want to have accurate airspeed info for your landings and such. Gps will only give you ground speed.
some cheap servos on amazon. they are almost identical to these but i think the exact ones i am using are discontinued. i ordered new servos and they arrived today but they are not working. i am sure it is not the servos because on an arduino running the "sweep" program the servos run perfectly