Well, to me, running is just correcting my posture 180 times per minute regardless. It can be easier to focus on the pelvis and lumbar spine since the propulsion is mostly coming from the obliques. But obviously neck and shoulder carriage are super important, more so for those of us with problems there.
I'd start with letting someone watch you run, paying attention to your neck (are you sticking it out, letting your head hang forward, or throwing it back?), shoulders (relaxed or up by your ears?), and arm swing (relaxed, symmetrical, hands near the nipple line, elbows never passing in front of the spine, hands never crossing the sternum?). That might at least point out any big issues you're having.
I'll cue myself explicitly on all of the above. Then some smaller details. Making sure my hands are relaxed. I draw an imaginary line from roughly T5 (right between the shoulderblades) to the occiput and lift through that line - that helps straighten out the "computer neck" without pulling my shoulderblades back off my ribs excessively. Keeping the eyes up so that I can watch the road ahead without throwing my neck back.
Then lower body good form, making sure your foot strike is not in front of your center of gravity, leveling your pelvis after every step, keeping your cadence up, "needle in cotton" and all that, will reduce impact and compression.
HTH...