I am in the continual process of improving my '84 245 and now I am looking at transmission options. I have the stock AW-70 in the car now and it does alright, but it leaks fluid badly and sometimes has a hard 1-2 shift at parking lot speeds. I got a quote from a reputable transmission shop for about $275 to repair all the leaks and flush the transmission. Not too bad in my opinion, but I still wonder about the 1-2 shift quality.
Today , I went to the local salvage yard and was looking at a '93 940 with an automatic transmission. The car was totaled when the passenger side front suspension collapsed at speed and crumpled into the footwell. I looked at the VIN plate and found this car has a lock-up AW transmission (code 6). Further research shows it has a AW-72, which has been recommended by members of TurboBricks for swapping into a 240. My interest in the swap lies in gaining a lock-up torque converter.
Will this work on an earlier car that needs the extension housing for the speedometer cable drive? I have heard the extension housings are swappable from AW-70->71, but will they swap from 70/71 -> 72? Can the speedometer drive gear be driven onto the output shaft of an AW-72 transmission? Has anyone done this before?

Thanks,
Nick