Sun Microsystems SPARC classic Service Manual page 87

Main logic board
Speaker/power
LED assembly
System I/O board
UNIT BOTTOM
Main logic board extractor lever
Removing and Replacing the Main Logic Board
FIGURE 8-6
6. Remove the system I/O board.
1. On the SPARCclassic X terminal, pull the plastic connector covers off the inactive
ports to gain access to the screws.
Chapter 8 Major Subassemblies 8-11