To remove the key lock, refer to Section 90-36 step 1 through 11 in the attached pages from the 1969 Buick Chassis Service Manual. These instructions are for the non-tilt column.
The associated switches and connectors are mounted along the column inside the passenger compartment. See drawings in the attachment. You may have to send a picture of the parts you received to insure correct identification.
If if this is not enough information, I can send added data from the manual. We will keep going until the repairs are complete.