It would be nice to at least know if the newer engine could be swapped into the old 240s. Eventually they are going to turn up from car wrecks.
It is probably a given that the transmission has to go in as well. Maybe the rear end too. If a guy had access to all components of a wreck it might be doable. Are you ever going to need a shop manual for this one Tom.
It is still the best way to modernise the injection system if everything can be squeezed in there. Should kill a weekend easily.