An 87 260E does not have a pollen filter. The filter was added in 94 (or maybe 93).
Don't leave it too long before replacing the blower if it is very noisy. It could damage the electronic speed control module (expensive) if the blower is drawing excess current or if it seizes up.
You will see this module when you get to the blower. Clean the heat sink fins to give better heat transfer while you are there.
Transmission fluid on the blower motor bushings can extend the life of the blower if the brushes are OK and bushings are not damaged from running too long dry.