I have used a Hurst Mystery shifter on a SM318 with a BW over drive. I don't think a 318 is that much different than a 319. Hurst built a bracket for an OD in the 60's. I have seen them on eBay, but it wouldn't be that difficult to fabricate. Room has to be left for the shift solenoid. The trickiest thing is clocking the shift levers. I have made them work by cutting the lever at the transmission in an arc conforming to the arc on the levers. I then put everything in neutral and weld it. Its not quite as simple as it sounds, but it works with a little trial and error. Care must also be taken that the throw is correct. You want to make sure the transmission goes all the way in gear. This sometimes requires shortening the levers a little.