To do that you can run the stplatformupdater.exe on the machine you will create your base image on. When the agent install completes and prompts you to register (either through the cloud or to a console) you can cancel the wizard. You now have the base agent installed. Next you need to register once each machine is imaged. To do this you simply script the following on the machine that gets imaged. This should occur after machine name change, SSID change, etc. This should be a unique machine at this point.
In c:\Program Files (x86)\LANDesk\Shavlik Protect Agent\ run the following:
STAgentManagment.exe -register -p silent -p serverURI=consolename.domain.com -p policy=mypolicyname -p passphrase="Your passphrase here"
You can get a full list of switches for stagentmanagement.exe by using /? from the command line.
I suggest using passphrase as you do not want to script a user name and password in here. Details on scripting an agent install can be found in the help > index under Manual agent installation script if you would prefer to do a full scripted install. The only difference is that is the full agent install, in the example above we installed the base agent and now just need to register. I would say either is about the same level of effort.