The '67 console has a few differences.
1) The plastic console base had a smooth finish on 65 and most '66's. In late '66 Buick went to a textured plastic base that kinda matches texture of the vinyl on the seats.
2) '67 GS shifter goes thru the floor in a different place than 65-66. This is to provide clearance for the linkage since the ST400 tail is under the 65-66 shifter location... and there isn't much room there. '67 shifter also uses a floor 'hump' and different rubber boot.
If you have ALL the '67 components... shifter, floor hump and boot, you can install them. You will have to cut another hole in the floor.
I do have a ST400 in my blue '66. I had to bend and grind the shifter linkage for clearance.
To provide more travel for the extra '1' gear position, I drilled another hole in the shifter's thru-the-floor lever. This provides extra leverage, and more travel for the st400 p-r-n-d--2-1 positions. Also made up a custom detent plate for each of the p-r-d-n-d-2-1 positions.
Easier option is to use the 65-66 shifter and buy a cable conversion kit from Shiftworks, $140:
http://www.shiftworks.com/buick.htm
