So I’m planning on buying another pair of front steering knuckles (with bearings and all still attached) so I can run 20mm 5x114 spacers and grind down the studs so the spare set of wheels I have can sit flush on the spacers… but back to my question, are the ucf10 steering knuckles compatible in ucf20’s ?

 

Yes they are compatible from 1990-2000. The ABS Sensors are different so you'll have to swap the sensors, I know the 90-92 sensors are different from 93-94.

 

the lower balljoints are different for 95-00 UCF20 cars vs UCF10