Deluxe heater fan makes awful noise

[cppursell]

Hey there, everyone. Here's my current dilemma with my '67 Chevy step-side C10:

As I was getting the truck ready for the road, I made sure the heater worked properly, so I took the inner fender out and cleaned out the heater core enclosure thing (which was filled with dirt and leaves). After I reinstalled it and put everything back together again, the old heater core decided to retire by leaking profusely... to my mild frustration I bought a new heater core, disassembled, replaced, and re-assembled yet again :P.

Right now, I'm getting great heat from this heater; it works fine. One thing though: when the fan is on it makes this horrible screeching noise for a couple minutes before it finally shuts up (especially when I start it cold). I want to get rid of this nuisance ASAP (especially 'cause it's winter).

Are there any ways to get the motor or fan or whatever is causing the noise to be quiet; by drilling in a certain spot and oiling it, or lubing a specific area, or is just replacing the fan motor the best solution?

Thanks ahead for your responses!