Lowering Spindle Problem

[62much]

Just installed BelTech 3" Lowering Spindles on my 69 c10. I had already installed 2" drop springs. The problem I ran into is that the new spindles mounting area (where it sits on the ball joints) is thinner, leaving the ball joint studs to long, as to not allow me to use a cotter pin in the castle nut, because when I tighten up the nut, there's about a 1/2" to the cotter pin hole on the stud. Hope this makes sense, plus the spindle just about contacts the upper control arm... real close. I used some HD thicker washers to make up the extra thread space, so I could safely put on the castle nut and secure it with a pin. This doesn't seem right to me. Has anyone else had this problem, and is my fix Okay? I don't know why I always run into these strange cases

Thanks
Clay