the main thing with the msutang II is that the suspension is made for hot rods, most being cars that came originaly with horible suspension, or even beam front axels, so the the double controll arm designe works great as a replacement for thes types of cars beacue you dont need to fab in any upper strut locating points, the whole suspension is contained! it will cruise on the highway or around town way better than than the chevy II suspension or a model A beam axel, but it is by no means a performance design, and therefor, it would be cheaper and mor benificial to just use the stock datsun suspension. I personaly went with a corvette c-4 front end for a front double a arm design for a performance aplication