Naming during OSD (non MDT) <Entry><Serial>

[joeman1881]

Good Morning,

I've been trying to find a solution for this one for a while now.  In our environment, we typically use the OSDComputerName TS variable to manually name devices.  We have about 15 sites and will be rolling out a large count of devices shortly which will be imaged in a centralized location then spread amongst these sites.  My thought is to name each device with <site code><serial>.  I've been able to name the device with a simple PS to make the name "DL-<Serial>", but that's because I set the "DL-" portion in the PS script.  I'm making about 300 flash drives for imaging and want the TS to prompt for OSDComputerName as usual, but then take that 5-digit entry, append the serial, and make the name those characters combined.  I found a few samples online, but non seem to properly prompt during OSD.  Has anyone successfully pulled this off with a standard Endpoint TS? 

Thanks in advance!