Heater Box
That may be what it is.
My recollection is the position of the box is dictated mostly by the blower, heater core hose connections, and then the hook to the cowl.
I don't recall any play in the blower mounting.
It's possible an aftermarket heater core is throwing the position off a little.
Both of these are replacement cores but the one on the right installs without damaging the box.
Wrong Tube routing ----------------------------------------Correct tube routing
That may be what it is.
My recollection is the position of the box is dictated mostly by the blower, heater core hose connections, and then the hook to the cowl.
I don't recall any play in the blower mounting.
It's possible an aftermarket heater core is throwing the position off a little.
Both of these are replacement cores but the one on the right installs without damaging the box.
Wrong Tube routing ----------------------------------------Correct tube routing