Drew,
Be sure and
1)use a bottoming tap to clean out the holes on the rack clamp bolts. Lots of junk down there.
2)I used pieces of rubber bicycle inner tube glued to the rack clamps to help secure the rack and keep it from moving.
3)If replacing bolts like I did measure carefully as bolts were bottoming out and rack did not tighten properly. Interesting handling till I figured that out in short order.
4) Replace pinch bolt and nut with new hardware. Use a metal locking nut not a Nylon Nylock Nut
5) Frank already talked about spacers and shims.
6) I replaced the pinion gear on my '68 rack. Gear is really cheap for the early racks, expensive for later racks. It did tighten up steering feel. There is a procedure in the manual on spacers required. Spacers can be made easily from hobby store copper sheet. Comes in various thickness. Without correct spacers rack will lock up or be stiff to turn. Don't ask me how I know on that one.
7) You've read the debate on grease vs. 90W gear oil. I won't reopen that debate.