Industrial Chassis' fixture holds the axle at the kingpin boss, while a press pushes down on the perch boss, with a pin inside the boss to retain its shape. The pin locates in the lower section of the fixture at full drop. A gas torch is used to maintain heat in the axle end throughout the procedure. Industrial Chassis' Adam Young told us that while they'll drop early Ford car and Ford truck axles, Chevy car axles have weird bends and are hard to get straight. They've done them in the past, but "it's hard to justify the cost involved," according to Adam. Industrial Chassis also has a press to drop steering arms on early Ford spindles, which keeps the Ackermann angle correct.