Darrell,
The 3630 power supply is there (I didn't check on the 8648). If you go to the main Agilent page and type in "E3630A" in the search box it will display a list of manuals and guides. The "E3630A Triple Output DC Power Supply Operating Manual" contains the schematic (pages 26,27).
The search seems to be finicky with part numbers.
(* jcl *)
FWIW -
Many times HP/Agilent (And others...) schematics are published in the manuals - To get the schematic, you have to purchase the manual or have the original manual that shipped with the product. When I run into this, I am often able to purchase the manual on ebay for less than $10.00 USD.
Best regards.