Hmm. Did that kit come with installation instructions that address bump steer? Or, are you just "on your own"?
The mounting point elevation of the steering rack is critical. The length of the steering links that connect the rack to the steering arms at the wheel hub is also critical (To completely neutralize bump steer, the steering rack may have to be either narrowed or widened between the inner ball joints in order to lengthen or shorten the steering links).
You may be able to get at least a feel for what will be involved. You have severe bump toe-in/ droop toe-out. Whether the steering rack needs to be mounted higher up or lower, depends on whether the steering rack is forward of the axle center line or aft of the axle center line. If the rack is forward of the axles, the rack would have to be raised. If the rack is aft of the axles, the rack would have to be lowered. As a wild guess from the severity you describe, the rack may have to be moved up or down an inch or more. You have to get the rack in the right elevation (trial and error) before you can begin to tell if or how much the length of the steering links have to be changed.
I've done a fair amount of bump steer work on production based race cars in my time. I'm located near Medford, OR and will be coming down to Sears Point to crew for a friend at the CSRG Charity Challenge, Oct 5-7. If you will be there, I'll be glad to look at your car and see if there is any more advice that I can offer.
Cheers,
David