Josh,
I'd suggest calling a manufacturer of drop spindles for your application. Get the engineer on the phone and find out the ball joint center to spindle centerline dimension for the spindle you want to use (yes you will need drops with that size tire).
The only other piece of information you MUST have is the height difference from the bottom of the frame to the LCA mounting hole in the front crossmember. You can figure everything else out from there. Maybe you can get someone who has one apart to measure the frame for you...
(no it's not mine, sorry)