There is a lot more technical information available from the OEM here:
http://www.ucfamerica.com/tech.htmlI just skimmed thru it, but it would appear from the size of the mounting bolt holes and pattern, that it is the installer's obligation to set the separately available mounting plates square and true to the frame at the time of installation, thus fixing the alignment once the half axle assemblies are bolted up. In short, it does not appear that there is any provision for alignment after installation.
Why do you want to pick such an over spec'd load rating? On the 8th pg of the
FAQ .pdf there is info about de-rating.
Here is the part that everyone forgets when they think that half axles are the solution for a drop floor design; the OEM specifies that a cross member be located between the mounting plates when retrofitting to half axles, "Unless already present it will be necessary to put a cross member on the frame in order to weld base plates, to which the Flexiride® Half Axles are bolted."
So if you need a cross member any way (which you appear to have shown) then why go to the extra expense and difficulty of installing half axles, when a full torsion axle is easier to align and, IIRC, less expensive?