Not sure how many folks out there used the technical guidebooks but at my company we have the technical guidebooks gooing back for 3-4 generations. These are outstanding references and have provided extremely useful documentation. In particular during the initial setups as well as later on when deciding to upgrade servers it's worth it's weight to help you determine memory configurations, and slot priorities.
I truly hope that the guidebooks are just delayed and will be made availabe soon! Hopefully Dell has not decided to stop making these available, as to do so would just make it more difiicult for the system administartors and eventually end up creating longer outages and require administrators to tie up time from the Dell support technicians.Quite often our technicians use the pictures to reference motherboard layouts.
As a company we generally download these documents once and maintain them on our SharePoint sites so that we have them locally. Hopefully others will chime in if they have more information.
Thanks...David