How to connect an Turbine engine to a Wing

Another way is to just place the turbine where you wish. Then use the Part Connection Tool to choose what part you wish to connect it to.
Be sure to turn auto resize off so the new parts dont match the old parts size and dimensions.
Look at the cargo drone built. Parts really dont even need to be near anything to actually connect. Its a bit of a cheat if you ask me but im lazy in career mode so i do it.

I usually don’t bother with direct connections. I like to hide a strut or fuel tank inside the wing and slap things on that way. It’s technically accurate, so it doesn’t bother me :p