I have been trying to put a Blasto J15 in a fuselage block to make a the back of a X-85 Goblin. I need any help but I'm not downloading anymore mods i want to do it with in game features but in desperation I will take a mod. Also i wish it was already a in game thing.
Nudge it or make the fusalage really small and place the motor on top of it then make the fusalage bigger
Nudge it in
Use the part transform tool. Click on a part, press the arrow on the right side of the screen and from that menu press the wrench in a gear icon.