Idler Pulley but for What?

[wunderwerks]

I picked up a box of these NOS pulleys at an auction thinking I could use them on my 65/66 SBF. But I can't match them up with any application so far. The bearing shaft number is a C4 and matches perfectly with the bearing shaft # for 65/66 adjustable and fixed AC idler pulleys. However the bracket is quite different. The pulley is .500" by 3.75" dia. Does anyone recognize this bracket and pulley?

 

[Fordestes]

I have one just like it , It was from a dealer installed air conditioner , the bearing is a serviceable part, not much use without the rest of the brackets etc.
fordestes

 

[alt63bird]

Possibly for '64 or '65 T-bird/Ford with 390?

 

[Ford blue blood]

Looks like the one on my 65 Bird. It is a factory air car, all original.

 

[Rowdy]

I have one just like it in my parts pile. Was thinking it has C2 in the prefix, but I may be mistaken. Rod