Agilent Technologies 89410A Service Manual page 178

Replacing Assemblies
To remove digital motherboard
5
Unplug all assemblies from the A90 Digital Motherboard. To
unplug the assembly behind cover #3, remove assembly
attached to cover #3.
7
Disconnect the display cable from the A90 Digital
Motherboard.
3-24
6
Using a T-15 torx driver, remove the four screws from the
power supply shield. Remove the power supply shield.
8
Using a T-10 torx driver, remove the eight screws from the
A90 Digital Motherboard.