Burgie,
My experience with steering boxes was with older units than '64, but what the heck...here and a few things I remember. The box is very simple...on mine, the balls, as in bearings, were not captured in a cage..be prepared to grab them as the fall out! When reassembling, use a heavy grease to hold them in place. Adjustment is straight forward. I think the worm is adjusted by removing thin paper shims on the bottom bearing retainer. The sector might be the same situation. Adjust to remove endplay but don't get them tight.
Worm to sector backlash, which gives you your steering play is adjusted with the small adjusting screw/locknut on the cover of the box. This is adjusted with the wheels straight ahead. adjust it to get rid of freeplay...with wheels straight ahead..then turn side to side. You should have no binding at the outer extremes. If you have binding, it's too tight.
Remember, the box has turned a million corners so it won't be factory tight, but should be acceptable. Fill it with 90w and your on your way! Gee, what did I forget?? :confused:
Stuart.