So Brendan I take you've found chains that aren't obstructed by the rear brake calipers? I guess chain design technology has greatly improved since my futile attempt at installing them on my Cobra 4+ decades ago. At the time the only alternative I could found that cleared them were individual cables that wrapped around the tires and were secured to the wheels between the spokes. I only used them when I got stuck, usually in some unpaved parking area, then immediately removed them once clear. The Salisbury POWR-LOK differential worked surprisingly well on icy roads. After all these years one incident still stands out in my feeble memory. I was driving in an ice covered parking area up a slight incline. A woman was driving some unknown brand sedan in the opposite direction and was spinning her wheels and sliding all over the place. I easily maneuvered around her and got to my desired destination with no loss of traction. No chains, cables or spikes!
Since then I have been living in sunny California and chains and the like have become a non issue.