I have seen this conversion before in a 1972 144, but not sure how much fabrication has been done in terms of mounting and wiring, as well as the HVAC unit and controls. For 73-74 144s, no major problems/fabrication required mounting it in. Also, the HVAC flaps are vacuum operated, with the same big three buttons on the center console.

If yours is a pre '72 model, you will have to replace your long shifter with a short one in order to fit the 240 center consle - probably the biggest obstacle that you have accomplished.

We even have a 122 here with a customized center console made from fiberglass that houses the stereo, HVAC vents and controls and speakers. Looks very nice. He overcame the shifter problem by relocating the shifter...by converting to an AW-71, with the shifter console from the 240 donor car. Looks stock.