Xerox Phaser 3300 Servce Manual page 212

Service Parts Disassembly
8-60
Caution
Reassembling CCDM
When refitting the Scanner Belt and Belt Spring take care to relocate the
tension spring as close to the right side of the CCDM as is possible, as
shown below.
When refitting the Scan Upper Cover take care to ensure that the Cover
Open Switch is not trapped.
s3300mfp-031
Phaser 3300MFP Service Manual