My house was built in 1975 and I pretty obviously have a "Rule of 6" GE main panel (the meter is above this)
My father-in-law (who has taught me a great many DIY things) swears that the neutral bus here is done wrong. (I didn't dare open the top where the meter is, but the bus extends above so I presume the service neutral connects up there.) I won't say he's outright wrong, but with this being the main panel, it looks acceptable to me (inasmuch as a panel of this age can be). I suspect the thick bare ground goes to a rod inside the slab, but I can't open the wall either to check, and I have no ground rods outside the box.
Is this passable, or is the only acceptable way to bond through a binding screw?