Ive just done this conversion and did exactly what BD has said.
Swap ecus, rewire maf (clean it with MAF cleaner while your there, cafefully)
Flipped the steering column which did give more room for the exhaust downpipe.
Used orange top 850 injectors also, just plug then in with new orings and have them serviced beforehand
Clean out your flame trap
Theres a few ways to mount the rad and cooler. As explained above it will make sense when you have it lined up. We used a set of the top brackets on the bottom for our efan and made a simple L bracket to hold the top of the rad to the cooler. Essentially the cooler sits where the rad does and you just need to mount the rad somehow. I can take photos if you like.
Fit an aw71 if you can if not already
Depending on your ecu you may get an engine light like I do. Its the egr from the 940 which the 240 does not have. Ive read somewhere that one can ground or ‘wire it up’ to be tricked into staying off.