I will first say that with a 325HP mill you really dont need a 4 link unless for handling purposes on the street. It this case a Three link is probably better.
The drag racing style rod ends are as good as they get. I am using 3/4 inch with hard races, no urethane crap. Those will wear out and will have the slop you are talking about. As for the bars I would bought a CE kit. It comes with 1 inch ID Chrome Moly Bars with 1/8 wall. That is some damned strong stuff. You have to get the pro kit, not the cheap one though. Also buy the best rod ends. They will run you about $50 each. As for the track locator, a diagonal link works very well and keeps thing straight on launch. Dont use a panard bar as it will cause the rearend to shift in the arc of travel. As for the hop, it is usually due to improper set up. A good rule of thumb for a mild setup is locate the bottom bar at 3 degrees down and the top bar in the highest hole possible. This is suppose to be a good starting point.