I ran into similar questions when building my locost (84 celica GTS donor). I swapped the uprights side-to-side to make them front-steer to accommodate the modified spitfire steering gear. This give the car negative ackerman (toe in during steer).
I dont want to make comment on the parts you have without seeing them, so Ill keep it pretty general.
Running the negative ackerman the car drove fine on the street. I aligned it with with reasonable front toe-out (~0.25-0.5") and the car has a notably long wheelbase 100+". I began drifting the car at local events and it was difficult to control at high counter-steer MA. Redeveloping the steering knuckles to allow for zero-to-positive levels of ackerman made the car way easier to drive at high slip angles, but the car is slower due to the front tires dragging I presume.
Even if your plan is not drifting, toe out will help you recover from spins (think high countersteer). Static toe (alightment) and dynamic toe (ackerman) are useful for controlling initial toe for turn in, and toe at high steering angles. Drag must be balanced through the both of them.
FWIW, my car was last setup with low positive ackerman and high static toe (~0.75" out) to make it tossable and stable at high slip angle. Its a toy that I built in college though, not a seriously developed race or production car.