RK05 drive foam deterioration and replacement

I just picked up an RK05AA drive, unknown condition but it appears in good shape internally. As I was going through a detailed inspection, I touched the foam that surrounds the air duct that connects to the access door on the cartridge, delivering clean air. The foam flaked off and seems to be deteriorating. Not as badly as the foam used in Selectric typewriters, which has turned to sludge after a few decades, but not something I want releasing particles into an air stream that will flow under the heads. Is this a known issue with the drives? What do people who restore/repair these do to eliminate this source of contamination into the cartridge? I would like to address this before I install a new absolute filter. Any tips for a substitute for the CE pack when I get to the point of loading heads and adjusting the drive? Carl ________________________________ This e-mail message, including any attachments, is for the sole use of the person to whom it has been sent, and may contain information that is confidential or legally protected. If you are not the intended recipient or have received this message in error, you are not authorized to copy, distribute, or otherwise use this message or its attachments. Please notify the sender immediately by return e-mail and permanently delete this message and any attachments. Gartner makes no warranty that this e-mail is error or virus free.