My observation is that the short shaft steering gear boxes were used right off the bat in 67 when a tilt steering column was ordered. Otherwise, the long 65-66 type was utilized. At some point (others will most likely shed light on this..."mid 67") the long shaft versions were phased out and everything was short. This was before the 1968 job one date. Also, there was no (per my understanding) collapsible column in 67 - those were one of the changes introduced in 1968.
With your date, I would think that a short shaft, but non-collapsible column, would be correct. Are you certain that yours is collapsible? Pictures might help.