I am modifying my 1972 Cutlass S to have bucket seats and a console/floor shift. Everything is in and working well but I still need some guidance. First, I was told there would be a plug for the console lighting located under the dash even though this car was not equipped with a console. Is this true and, if so, what would be its approximate location? Second, I have the proper steering column which I still need to re-key. What is the linkage setup for this column to the THM350 transmission? Thanks in advance!

 

Behind your clock/blank, to the right of the speedo, there is a plug that an "extension" harness plugs into. That runs down to where the front of the console would be then you plug the "console" harness into that. They both need to be from a '71-'72 car, a '70 will not work. I might have these.
You will need the back drive linkage that came on all automatic cars. It will connect at the bottom of the column & to to a pivot on the frame & then into the shift selector lever on the side of the trans. The console cars had a special lever to hold the end of the shift cable. I have all the parts except for the cable.

 

The plug for the console harness is built into every dash harness. It's located to the right of the steering column. The Assembly Manual has a good drawing of this.

If by "proper steering column" you mean a floor shift column, just reuse the old column shift linkage rods from your old column. The Chassis Service Manual shows you how to adjust this linkage. Note that the bracket that goes on the trans is unique to floor shift cars and has provisions for attaching both the shift cable and the backdrive linkage. Repros are available if you don't have this bracket.

You can also simply swap the lock cylinder from the old column to the new one. You don't need to rekey anything.

 

You were right on with the location thank you!