I am no suspension expert but I would recommend that you read some of Ron Sutton's suspension posts. There is a lot of discussion on several styles of link rear suspensions available on the aftermarket these days. Some will allow you to use the 12bolt if that is the route you want to go. I have a 12bolt and I found it less costly to buy a new Moser 9" floater than to rebuild the 12bolt. As for link suspensions, Ridetech just recently released a line of link rod ends that are supposed to reduce suspension noise among other things.
https://www.ridetech.com/products/r-joint-en/