Force it & when it strips out, try Beemer Boneyard for a used throttle body etc. Before reassembly of both throttle bodies, clean the ports, bodies, & BBSs thoroughly with carb cleaner.
Use a flashlite to set the throttle stops for the tinyest opening off of closed (like +1/8 turn), and the BBSs 1 1/2 turn out. Assemble & readjust those throttle stops for balanced and correct idle, then set the TPS for .385 V.
If necessary, tweek the BBSs for final idle balance.