Help: I need to Identify an OEM Blower Motor for A/C truck

[70LonghornCST]

Hello! I am looking at buying an OEM blower motor for my air conditioned truck and I believe that there is an A/C version, and a non-A/C version. The person from whom I am looking at puchasing the blower motor is not sure, but has indicated that his "Fan unit is marked with a big " H " (Harrison, I think) and has # 3157437 on it."

Also, his has a plastic fan, wheras my original had a metal fan. If you know for sure, please let me know. I have long since disposed of my original blower motor, and kept my fan. However, my fan needs replacing. I want to go OEM, not aftermarket, which is why I am bothering with a used OEM.

Thank you for you help.