In the 260Z take out the air vent panel and the square-ish shaped heater matrix behind it. You'll need to remove the side brackets that mount the front panel. There are 2 screw at the rear of the matrix on the top both left and right side, you only need to loosen them as the matrix only slides over them which also means that the tabs are easy to break so go slowly. Once you have that out you'll have heaps of access. Get a light and a mirror and start feelin around.