On a mini truck axle cut and turn knuckle balls ~180*, flip the axle upside down, and install the third right side up (or upside down in relation to what you started with).  IIRC 4 studs don't line up and will have to be relocated when installing the third upside down (also some grinding for clearance).

I'm not sure how much of this translates to the 40 series...but pull the third and try to install it upside down to see how much will need to be modified.

To save yourself the headache look into a ruffstuff housing in the driver's drop flavor.  They're very reasonably priced assuming you use your knuckle balls/third/etc (just buy the bare housing).