I have to state the obvious,,, find out what the problem is and take care of it immediately. Who put in the outer bearing and did he have his head out of his arse when he did it? He did change the race too,,,, didn't he? The race was seated, bearing packed and preload set correctly? When the outer bearing was done the inner bearing was checked, cleaned and packed? (Damn well should have been, the bearings in the other wheel should have been gone over, cleaned, checked and packed at the same too.. Again common sense, if one goes out,, better check all those front bearings,,, or stumble along in ignorant bliss)
"Should I change the inner one too?" Common sense should tell you that if the bearing, or bearings, are still good they don't have to be replaced. If they are pitted or eroded, replace them. You (or us on the BB) will never know unless they're taken out, cleaned and inspected then correctly repacked and reinstalled.
Last,, The brakes themselves (on both sides) were checked over when drum(s) was off?
I drive a 68 Impala and once had strange noises coming from my front end. I immediately took it apart and found the leading brake shoe hanger had actually cracked and was barely hanging there. I hate to think what would have happened if it had entirely broken off, got crosswise and locked up the wheel as I was tooling down the road. At the very least it would have torn everything up inside the drum and very probably would/could have thrown me off the road.
Unless you know what you are doing things like this deserve to be looked at by experts,, for safety sakes. Around here we have several pros like "Brake Masters" or "Midias" who will inspect your brakes and bearings for free and tell you what it needs before doing anything or charging you anything. If anything does REALLY have to be done they can do it right away, gaurantee the work, usually for a reasonable price (brake work is a very competitive business).
Hey,,, you owe it to yourself, "grinding type noises" are not normal. You're dealing with a car that's 40 years old and you just plain have to stay up on the maintence if you want a safe ride.