FYI, I dug up my old kit car catalog this past weekend.
They list the standard shortrack spindle as P4007846 and 47 as Rt and Lt respectively. Disc is P3690910. The Grand National spindles are P4007302 and 03 as Rt and Lt and P4007333 is the disc.
Other tid bits of info; the standard kit car rotor used 3580892 inner and 3580888 outer wheel bearings, 2298534 upper ball joint and P3722512/P2835911 lwr ball joints. Interestingly enough, P4007773 ball joint repair kit was also available. Other service items such as seals, dust cap, pins, bolts all had standard service part numbers. All the corresponding parts in the Grand National set up had P prefix on all of them.
I haven't dug up my Hollander yet to see what, if any, changeovers I could even relate to those since Chrysler uses the P prefix on all performance parts and those tended to be seperate from regular service parts.
Kit Car T-Bars ranged from 1.06 to 1.38 at 654# of wheel rate. I'm real curious about what the sockets those anchored in looked like. The rear unit was an indexable kit that could be set up with a cockpit adjustable ride height provision.