I have a 1981 f100 300 inline 4spd srod. I believe its non ac because there is no ac vents in the dash. The heater blower motor is going out. I'm seeing two different heater motors for my truck at the parts store. One is for ac and other is for non ac. In the pics the ac motor has a metal plate attached to it but the non ac motor does not have a metal plate. Well looking at mine under the hood on the heater box the blower has this plate. So I don't know if someone swapped to a ac heater box or maybe my truck came with ac or if its just the parts place has the parts labeled wrong. Anyone had this same issue or can give info? Thanks

 

I think the best thing would be to pull the fan/motor, and carry it into a parts store. That way you can compare the new to the old, and know that you have the right part when you leave.

 

Here's the non-A/C setup.

 

That is what my blower looks like. Autozone and lmc shows it to be the ac blower though...

 

Factory Air Blower Motor 35579: Shop the best Blower Motor at Advance Auto Parts
Here is a link to the blower just like mine but it to is labeled as a ac blower and mine should be a non ac