I'd make sure your stub axles are not scored, and get new ones if necessary.
When I reinstalled my vertical links, I had the same question you have about "how tight." Of course I was reassembling the front end and installing the trunions to the vertical links with no load, since the coil springs are removed at that point.
I called Harry at Moss Tech Support, now retired but someone I really liked and relied on, and he said you can tell instinctively.
He explained that when you put the trunion on, greased of course, it should not feel tight because it will then bind on a turn, and that if you put it on as far as possible with no binding on regular turns (meaning within the intended steering limits in both directions), with the trunion seal properly in place and not binding, it will be right.
I spent a few minutes studying each side, and he was right. The trunion will only go on so far, and still move freely without binding.
If one of yours is tight, I'd find out why and address the issue.
I'm not sure what you mean by the steering wheel not centering itself. If yours is like mine, then after putting the new bushings on, you may well have to loosen the upper bracket, pop the steering rod up and refit the rod into the splines. Not sure that's your issue, but whenever I'm messing with the bushings, the steering will be off and must be reset. Resetting isn't easy either. I always miss by a little, and I'm sure others know some easy way that eludes me.
Good luck.