The blower is under a plastic plate secured with screws on the top of the firewall. It is a fairly easy replacement. Be sure to put some penetrating oil on the four screws holding the blower in as they rust and can break easily.

You might have a broken "cage" causing the noise rather than the motor.

Rebuilt units are readily available from Partshop and other suppliers.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe