I've got a Chevy 12 bolt in my car now. It uses the stock trailing arms and has Viking coil over shocks. The coil overs are bolted to the rear using UMI Performance brackets that bolt to the lower trailing arm mounts, and the coil overs bolt to those. The passenger side axle tube appears to be coming out of the differential (see photo). It was suggested to me to upgrade to one of the complete nine inch rears for 68-72 GM A bodies from Quick Performance rather than deal with a 50 year old rear end. I just got off the phone with QP and asked them if the lower trailing arm mounts on their nine inch would be similar enough to the ones on a stock 12 bolt that those UMI brackets could just be bolted right up. The guy didn't seem to think the trailing arm mounts would be exactly the same. Of course, that doesn't mean it WON'T work, it means we don't know. So I'm wondering how people have dealt with this, coil over shocks on a "bolt in" Ford nine inch in an A body. Alternatively, I've been asking around if anybody near me can weld the 12 bolt tube for me so I don't have to buy a rear end. The car is probably in the neighborhood of 475-500 hp and is street driven only, not raced. Any weld repair will need to make it hold up at least as well as when it was brand new.