72 360 to 89 318 swap
The 904 and 727 converters are different and the 89 is most likely a lockup. Plus the 360 is external balance and the 318 in neutral balance. You can grind the weight off your 360 converter to make it neutral balance to work with the 318. On the motor brackets you will have to use spacers because the 318 and 360 engine brackets are a little different as far as width. You will have to find a car (center sump) pan because the van will be rear sump. The 318 and 360 have a different pan sealing area so you can't swap pans. The heads on the '89 have air pump ports below the exhaust ports that may have to be plugged depending on the exhaust manifolds you are using. That should just about cover it.