It used to be an almost daily thing back when I was working at the Lincoln/Mercury dealership.
I can remember a couple of times having someone drive the car around while I was upside down with my head under the dash and my knees bent over the headrest of the seat, trying to find a damn rattle.
I have ridden around inside trunks and one time actually laid across a an engine on a damn Ford Taurus with the hood up while my buddy drove in circles as fast as I could hold on, trying to find a weird noise that only happened when the guy was making hard turns going one way. That one turned out to be a weak return spring for the starter gear. It would slide over and start hitting the ring gear on the flywheel.
Even with a fused lower back I used to have to get in some crazy assed positions underneath dashboards sometimes.
That was twenty years ago now. I ain’t nearly as flexible now as I was then.
I certainly don’t miss that fucking bullshit either.