Measure up mine - 3.5" back to back, which is exactly the same as the Asiatam Opel Blitz axles (I'm guessing the White company used a standard front axle design from the same folks who supplied GM?).

Asiatam axles available separately here: http://www.asiatam.com/index.php?cat...-3-Tonner.html

Could Ryan's SCX10 mod be made to work with these? The end caps of the diff housings are separate pieces, so in theory somebody could cast up a new part to hold a bearing and second pinion to drive a rear axle?