Temperature controller from a 78 work in a 74?
 

I’m picking up a 1078 C30 as a parts truck for my 1974 Suburban K20. The previous owner swapped an 89 Suburban front clip and gauges and dash and power doors in. The wiring is a total hack job and I want the 70’s look. One thing that’s jacked up is the temperature control switch (the entire assembly, not just the blower speed switch). The switch in the 78 is in decent shape. LMC shows a different assembly for 74-75 and for 76-78, but wasn’t sure if the appearance is what changed or if the wiring and vacuum lines changed as well. Does anyone know by chance? Would rather use that one than buy a new one 🤷🏼*♂️