Have existing install Flash and going to install to USB3 flash.

I have a right now 15 systems on order. New HP Compaq Elite 8300 Microtower PCs.

The first thing though is getting the USB 3 install flash to run correctly. I can get it to boot but it doesn't see the install files cause it doesn't read that it is in a USB 3 port once it is booted up. I was hoping to find or at least be pointed to a thread that explains the process of slipping drivers into an existing flash install drive. Basically I would like to do this for all the different USB 3 drivers I come across here at work. It makes my job much easier to add updates and have all the drivers I need right in one place then I can redo systems very quickly if there isn't a current image on hand for the system in question. It would be great if there is a tool that does it but if I could be pointed to a nice guide that does it step by step would be nice too.

The second I would like to do is install from flash to another usb 3 flash drive so that I have a diagnostic USB 3 flash. Fast boot and such whats not to like. It doesn't have to be from the flash install to the universal diagnostic flash but that would be nice to know how to do. The big thing is to get Windows 7 64 bit Enterprise booting and running on any machine that has USB 3 as well as 2. USB 2 isn't a problem but USB 3 is. Again though a tool would be great but a step by step guild would work well too.

I searched through the forums and I didn't want to do any necromancy on old dead threads for questions I have. :)

Anybody out there? So far What I have tried doesn't seem to work. I have been trying RT7 Lite and getting the USB 3 drivers added that way but so far I'm not having any luck. I suppose I could start from scratch instead of taking an existing ISO that has had mods done to it. Just how do I install the USB 3 drivers to the boot part of the flash installer?